github PR #259 - paranoid_confirmation:trap

Fairly old pull request from copperwater:  add new paranoid_confirm
setting 'trap'.

The old commit suffered from bit rot and merging needed too much
fixing up despite there not being many bands of change in the commit's
diffs.  I ultimately redid it from scratch, although the two biggest
chunks of code started with copy+paste of the pull request's commit.

It operates like paranoid:pray.  Setting paranoid:trap adds a new
"Really step into <trap>?" y/n prompt when attempting to move
into/onto a known trap, even if an object covers it on the map.
Setting both 'paranoid:Confirm trap' turns that into a yes/no prompt.
(Adding 'Confirm' affects other paranoid confirmations; in addition
to requiring yes<return> rather than just y to accept, it also forces
no<return> to reject.)

However, moving into a known trap that is considered to be harmless
behaves as if no trap was present.  Some of the trap classification
might be out of date; several types of traps have undergone changes
since implementation of the original pull request, notably anti-magic
field.  When the hero is hallucinating, all known traps are considered
harmful since the map no longer reliably describes them.

Preceding a movement command with the 'm' prefix also behaves as if
no trap was present, bypassing confirmation for that move, similar to
how paranoid:swim currently behaves.  Being stunned or confused also
behaves as if no trap was present, taking priority over hallucination.

This updates the documentation.

Supersedes #259
Closes #259

dat/opthelp

@@ -214,7 +214,7 @@ packorder     a list of default symbols for kinds of       [")[%?+!=/(*`0_]
 paranoid_confirmation  space separated list    [paranoid_confirm:pray swim]
               of situations where alternate prompting is desired
               Confirm -- when requiring "yes", also require "no" to reject;
-                      also requires yes rather than y for pray, Autoall
+                      also requires yes rather than y for pray, trap, Autoall
               quit    -- yes vs y to confirm quitting or to enter explore mode
               die     -- yes vs y to confirm dying (for explore or debug mode)
               bones   -- yes vs y to confirm saving bones data in debug mode
@@ -224,6 +224,7 @@ paranoid_confirmation  space separated list    [paranoid_confirm:pray swim]
               Were-change -- yes vs y to confirm changing form due to
                       lycanthropy when hero has polymorph control;
               pray    -- y to confirm an attempt to pray; on by default
+              trap    -- y to enter a known trap unless it is harmless;
               swim    -- require m prefix to move into water or lava when
                       hero has seen it and isn't impaired; on by default;
               AutoAll -- y to confirm if using menustyle:Full and choice 'A'