reduce the number of #seeXYZ commands

Noticed while working on Qt's extended command handling, there
are an awful lot of "seeXYZ" commands.  Keep the inventory display
ones (named versions of ')' to show wielded weapon(s), '[' for
worn armor, '"' for worn amulet, &c) and rename the others:
| #seenv     -> #wizseenv     debugging command
| #seespells -> #showspells   '+' command
| #seetrap   -> #showtrap     '^' command

Also, expand the descriptions of #shell and #suspend a bit in
the Guidebook.  LaTeX version is untested.

dat/wizhelp

@@ -13,7 +13,6 @@ Debug-Mode Quick Reference:
 #lightsources   == show mobile light sources
 #panic          == panic test (warning: current game will be terminated)
 #polyself       == polymorph self
-#seenv          == show seen vectors
 #stats          == show memory statistics
 #terrain        == show current level (more options than in normal play)
 #timeout        == look at timeout queue and hero's timed intrinsics
@@ -25,6 +24,7 @@ Debug-Mode Quick Reference:
 #wizmakemap     == recreate the current dungeon level
 #wizrumorcheck  == validate rumor indexing; also show first, second, and last
                    random engravings, epitaphs, and hallucinatory monsters
+#wizseenv       == show map locations' seen vectors
 #wizsmell       == smell a monster
 #wizwhere       == show dungeon placement of all special levels
 #wmode          == show wall modes