merge new use_menu_glyphs option with menu_objsyms

The two options are very similar but probably mutually exclusive
except when using look-here and look-into-container (both via ':')
with the default setting for 'sortloot', or with inventory when
'sortpack' has been toggled off.

This removes 'use_menu_glyphs' and changes 'menu_objsyms' from a
boolean to a compound taking six possible values:
| 0: no object symbols in menus,
| 1: append object class symbol to object header lines (same as old
|menu_objsyms boolean),
| 2: include object symbol in menu entry lines for objects (same as
|recently added use_menu_glyphs),
| 3: both 1 and 2,
| 4: display as #2 but only if the menu lacks class header lines,
| 5: if header lines are present, display as #1; if headers are not
|present, then display as #4 (which will implicitly be #2).
Default is #4.

Effectively replaces the options portion of pull request #1406 and
retains the functionality, but not as default for normal menus.

Guidebook.tex is only partially updated.  Someone else will need to
finish that.

include/flag.h

@@ -264,6 +264,8 @@ struct instance_flags {
     int getloc_filter;     /* GFILTER_foo */
     int in_lava_effects;   /* hack for Boots_off() */
     int last_msg;          /* indicator of last message player saw */
+    int menuobjsyms;       /* value of 'menu_objsyms' option;
+                            * ought to be in flags rather than iflags */
     int override_ID;       /* true to force full identification of objects */
     int parse_config_file_src;  /* hack for parse_config_line() */
     int purge_monsters;    /* # of dead monsters still on fmon list */
@@ -300,13 +302,13 @@ struct instance_flags {
      */
     unsigned msg_history; /* hint: # of top lines to save */
     int getpos_coords;    /* show coordinates when getting cursor position */
-    int menuinvertmode;  /* 0 = invert toggles every item;
-                            1 = invert skips 'all items' item */
+    int menuinvertmode;   /* 0 = invert toggles every item;
+                           * 1 = invert skips 'all items' item */
     color_attr menu_headings;    /* CLR_ and ATR_ for menu headings */
     uint32_t colorcount;    /* store how many colors terminal is capable of */
     boolean use_truecolor;  /* force use of truecolor */
 #ifdef ALTMETA
-    boolean altmeta;      /* Alt-c sends ESC c rather than M-c */
+    boolean altmeta;        /* Alt+c sends ESC c rather than M-c */
 #endif
     boolean autodescribe;     /* autodescribe mode in getpos() */
     boolean cbreak;           /* in cbreak mode, rogue format */
@@ -315,7 +317,8 @@ struct instance_flags {
     boolean echo;             /* 1 to echo characters */
     boolean force_invmenu;    /* always menu when handling inventory */
     boolean hilite_pile;      /* mark piles of objects with a hilite */
-    boolean menu_head_objsym; /* Show obj symbol in menu headings */
+    boolean menu_head_objsym; /* Show obj symbol in menu headings; controlled
+                               * by 'menuobjsyms' */
     boolean menu_overlay;     /* Draw menus over the map */
     boolean menu_requested;   /* Flag for overloaded use of 'm' prefix
                                * on some non-move commands */
@@ -334,7 +337,8 @@ struct instance_flags {
     boolean tux_penalty;      /* True iff hero is a monk and wearing a suit */
     boolean use_background_glyph; /* use background glyph when appropriate */
     boolean use_menu_color;   /* use color in menus; only if wc_color */
-    boolean use_menu_glyphs;  /* use object glyphs in menus, if the port supports it */
+    boolean use_menu_glyphs;  /* use object glyphs in menus, if the port
+                               * supports it; controlled by 'menuobjsyms' */
 #ifdef STATUS_HILITES
     long hilite_delta;        /* number of moves to leave a temp hilite lit */
     long unhilite_deadline; /* time when oldest temp hilite should be unlit */

include/optlist.h

@@ -442,9 +442,9 @@ static int optfn_##a(int, int, boolean, char *, char *);
                 No, Yes, No, No, NoAlias, "jump to the last page in a menu")
     NHOPTC(menu_next_page, Advanced, 4, opt_in, set_in_config,
                 No, Yes, No, No, NoAlias, "go to the next menu page")
-    NHOPTB(menu_objsyms, Advanced, 0, opt_in, set_in_game,
-                Off, Yes, No, No, NoAlias, &iflags.menu_head_objsym,
-           Term_False, "show object symbols in menus")
+    NHOPTC(menu_objsyms, Advanced, 12, opt_in, set_in_game,
+           Yes, Yes, No, Yes, "use_menu_glyphs",
+           "show object symbols in menus")
 #ifdef TTY_GRAPHICS
     NHOPTB(menu_overlay, Advanced, 0, opt_in, set_in_game,
            On, Yes, No, No, NoAlias, &iflags.menu_overlay, Term_False,
@@ -789,9 +789,6 @@ static int optfn_##a(int, int, boolean, char *, char *);
     NHOPTB(use_inverse, Advanced, 0, opt_out, set_in_game,
            On, Yes, No, No, NoAlias, &iflags.wc_inverse, Term_False,
            "display detected monsters in inverse")
-    NHOPTB(use_menu_glyphs, Advanced, 0, opt_out, set_in_game,
-           On, Yes, No, No, NoAlias, &iflags.use_menu_glyphs,
-           Term_False, "show object glyphs in menu items")
     NHOPTB(use_truecolor, Advanced, 0, opt_in, set_in_config,
                 Off, Yes, No, No, "use_truecolour",
            &iflags.use_truecolor, Term_False,