add some unicode support (trunk only)

This patch attempts to add some levels of unicode support
to NetHack.

The master on/off switch for any Unicode support is
defining UNICODE_SUPPORT in config.h. Currently
there is code support for two subsets of unicode support:

UNICODE_DRAWING

If UNICODE_DRAWING is defined, then the data
structures used to house drawing symbols are expanded
to the size of wchar_t, big enough to hold unicode characters.
A typdef called `nhsym' is involved and if UNICODE_DRAWING
is defined, it is wchar_t, otherwise it is uchar.

UNICODE_WIDEWINPORT

If UNICODE_WIDEWINPORT is defined, then the data
structures inside the window port are expanded to the size of
wchar_t, big enough to hold unicode characters.  Both map
symbols and text within the window port are expanded, in order
for potential support for displaying multinational characters some
day, but this patch only provides viewing of map symbols.
A typdef called `nhwchar' is involved and if UNICODE_WIDEWINPORT
is defined, it is wchar_t, otherwise it is char.

The only window port with code support for UNICODE_WIDEWINPORT
currently is the TTY port.  Don't enable UNICODE_WIDEWINPORT
unless:
- it is a TTY port
- the underlying platform specific routines can
handle the larger data structures.

Don't enable UNICODE_SUPPORT unless:
- your compiler can handle wchar_t.
- your compiler can accept L'a' characters.
- your compiler can accept L"wide" strings.

Note that if your compiler can handle the above, you could
enable the larger data structures (currently if TTY) even if your
platform can't actually display unicode or UTF-8, by messing
with u_putch() in win/tty/wintty.c to only deal regular chars.
That should be the only function that actually pushes wide characters
out to the display.

If you enable UNICODE_SUPPORT, and your platform is capable
you will need to turn on the unicode run-time option to be able to
load unicode character sets from the symbol file, to be able to
push unicode characters to the display. You'll also want to load
a unicode symbol set once the unicode option is toggled on. In
a config file you would do that via these two lines:
OPTIONS=unicode
OPTIONS=symset:Unicode_non_US

The repository was stamped with NETHACK_PRE_UNICODE
prior to applying this patch, and stamped with
NETHACK_POST_UNICODE afterwards. The code differences
between those two tagged versions are this patch.

dat/symbols

@@ -201,6 +201,10 @@ start: RogueEpyx
 	S_food: \x05			# club (as in cards)			
 	S_potion: \xad			# upside down '!'
 	S_scroll: \x0e			# musical note
+#	S_armor: \x5b
+#	S_ring: \x3d
+#	S_amulet: \x0c
+#	S_tool: \x28
 	S_wand: \xe7			# greek tau
 	S_coin: \x0f			# yes it's the same as gems
 	S_gem: \x0f			# fancy '*'
@@ -393,3 +397,131 @@ start: NHAccess
 	S_explode9: \047
 finish
 
+start: Unicode_US
+	Description: Unicode symbols similar to code page 437
+	Restrictions: Unicode
+	S_vwall:     U+2502		# box drawings light vertical
+	S_hwall:     U+2500		# box drawings light horizontal
+	S_tlcorn:    U+250C		# box drawings light down and right
+	S_trcorn:    U+2510		# box drawings light down and left
+	S_blcorn:    U+2514		# box drawings light up and right
+	S_brcorn:    U+2518		# box drawings light up and left
+	S_crwall:    U+253C		# box drawings light up and left
+	S_tuwall:    U+2534		# box drawings light up and horizontal
+	S_tdwall:    U+252C		# box drawings light down and horizontal
+	S_tlwall:    U+2524		# box drawings light vertical and left
+	S_trwall:    U+251C		# box drawings light vertical and right
+	S_ndoor:     U+2556		# box drawings down double and left single
+	S_vodoor:    U+25A0		# black square
+	S_hodoor:    U+25A0		# black square
+	S_bars:      U+2261		# identical to
+	S_tree:      U+00B1		# plus-minus sign
+	S_room:      U+00B7		# middle dot
+	S_corr:      U+2591		# light shade
+	S_litcorr:   U+2592		# medium shade
+	S_fountain:  U+2320		# top half integral 
+	S_pool:      U+2248		# almost equal to
+	S_ice:       U+00B7		# middle dot
+	S_lava:      U+2248		# almost equal to
+	S_vodbridge: U+00B7		# middle dot
+	S_hodbridge: U+00B7		# middle dot
+	S_water:     U+2248		# almost equal to
+	S_vbeam:     U+2502		# box drawings light vertical
+	S_hbeam:     U+2500		# box drawings light horizontal
+	S_sw_ml:     U+2502		# box drawings light vertical
+	S_sw_mr:     U+2502		# box drawings light vertical
+	S_explode4:  U+2502		# box drawings light vertical
+	S_explode6:  U+2502		# box drawings light vertical
+finish
+
+start: Unicode_non_US
+	Description: If default OEM CP for non-Unicode programs is not 437 or 850
+	Restrictions: Unicode
+	S_vwall:    U+2502		# box drawings light vertical
+	S_hwall:    U+2500		# box drawings light horizontal
+	S_tlcorn:   U+250C		# box drawings light down and right
+	S_trcorn:   U+2510		# box drawings light down and left
+	S_blcorn:   U+2514		# box drawings light up and right
+	S_brcorn:   U+2518		# box drawings light up and left
+	S_crwall:   U+253C		# box drawings light up and left
+	S_tuwall:   U+2534		# box drawings light up and horizontal
+	S_tdwall:   U+252C		# box drawings light down and horizontal
+	S_tlwall:   U+2524		# box drawings light vertical and left
+	S_trwall:   U+251C		# box drawings light vertical and right
+	S_vodoor:   U+25A0		# black square
+	S_hodoor:   U+25A0		# black square
+	S_corr:     U+2591		# light shade
+	S_litcorr:  U+2592		# medium shade
+	S_vbeam:    U+2502		# box drawings light vertical
+	S_hbeam:    U+2500		# box drawings light horizontal
+	S_sw_ml:    U+2502		# box drawings light vertical
+	S_sw_mr:    U+2502		# box drawings light vertical
+	S_explode4: U+2502		# box drawings light vertical
+	S_explode6: U+2502		# box drawings light vertical
+	S_coin:	    U+20AC		# euro
+finish
+
+start: UnicodeRogueEpyx
+	Description: Unicode Rogue level symbols
+	Restrictions: Unicode
+	Restrictions: Rogue
+	Color: Yes
+	S_weapon: 	U+2191		# up arrow
+	S_armor:  	U+25d9		# Vert rect with o
+	S_ring:	 	U+2642		# circle with arrow
+	S_amulet:	U+2640		# "female" symbol
+	S_food:		U+2663		# club (as in cards)			
+	S_potion:	U+00a1		# upside down '!'
+	S_scroll:	U+266a		# musical note
+	S_wand:		U+03c4		# greek tau
+	S_coin:		U+263c		# yes it's the same as gems
+	S_gem:		U+263c		# fancy '*'
+	S_rock:		U+0060		# grave accent
+	S_ball:		U+0030		# digit 0
+	S_chain:	U+005f		# low line
+	S_venom:	U+002e		# full stop
+	S_book: 	U+002b		# + sign
+	S_vwall:	U+2551		# all walls now use
+	S_hwall:	U+2550		#   double line graphics
+	S_tlcorn:	U+2554		# box drawing double down and right 
+	S_trcorn:	U+2557		# box drawing double down and left 
+	S_blcorn:	U+255a		# box drawing double up and right 
+	S_brcorn:	U+255d		# box drawing double up and left 
+	S_crwall:	U+256c		# box drawing double vertical and horizontal 
+	S_tuwall:	U+2569		# box drawing double up and horizontal 
+	S_tdwall:	U+2566		# box drawing double down and horizontal 
+	S_tlwall:	U+2563		# box drawing double vertical and left 
+	S_trwall:	U+2560		# box drawing double vertical and right 
+	S_ndoor:	U+256c		# box drawing double vertical and horizontal 
+	S_vodoor:	U+256c		# box drawing double vertical and horizontal 
+	S_hodoor: 	U+256c		# box drawing double vertical and horizontal 
+	S_room:		U+00b7		# centered dot 
+	S_corr: 	U+2592		# medium shade
+	S_litcorr:	U+2593		# dark shade
+	S_upstair:	U+001e		# Greek Xi 
+	S_dnstair:	U+001f 
+	S_arrow_trap:	U+2666		# diamond (cards) 
+	S_dart_trap:	U+2666
+	S_falling_rock_trap: U+2666
+	S_squeaky_board: U+2666
+	S_bear_trap: 	U+2666
+	S_land_mine:	U+2666
+	S_rolling_boulder_trap: U+2666
+	S_sleeping_gas_trap: U+2666
+	S_rust_trap:	U+2666
+	S_fire_trap:	U+2666 
+	S_pit:		U+2666
+	S_spiked_pit:	U+2666 
+	S_hole:		U+2666
+	S_trap_door:	U+2666
+	S_teleportation_trap: U+2666 
+	S_level_teleporter: U+2666
+	S_magic_portal: U+2666 
+	S_web: 		U+2666 
+	S_statue_trap:	U+2666 
+	S_magic_trap:	U+2666
+	S_anti_magic_trap: U+2666 
+	S_polymorph_trap: U+2666
+	S_human:	U+263a		# face
+finish
+