Deduplicate
Increase megazig lethality

Add a chance of placing the player in the middle of zig levels,
for zigs after the first cleared. Chance increases with depth &
megazig level.

Might make things a little dicier.

TODOs:
 - make it work with slime levels somehow
 - support placing pillars to either side of the start (on large
   levels)
Set a minimum Tiles window size of 800x480 when not using touch UI

Resizing the window too small can cause Tiles crashes. We might
consider allowing a smaller X limit. There is existing code to prevent
rc tiles options from using smaller than 800x480, so I kept the window
limits consistent with that.
Fix resizing of the Tiles window

The SDL event loop forced a redraw to display the current mouse cell's
alt. text, but these redraws were occurring not only when the mouse
moved. Moved this logic into the mouse movement handling section and
did some other refactoring.
Blow up another "blown up by" by crediting player wands correctly.
Move monster-hide relationships into data
Partially move hide->armour relationships into data

armour_is_hide() is trickier.
Don't make rN+ armour give monsters sInv

Looks like a copy-paste error introduced in 2edd8d46d6c6, just shy
of four years ago.
Make death scarab corpses less questionable

wheallssss......

(but seriously, autocorpses shouldn't require so much direct
intervention.)
Deduplicate hide armour listings

Performance reduced from O(1) to log(n) expected, O(n) worst case;
I doubt this is a problem, esp. given that n is quite small.

Some ugly code generating the set of dragon/troll armours; seems
like there must be a better way to do that.
Stop invigorating plants (Hangedman)

Ephemeral Infusion gets really spammy with ice blocks around,
otherwise.
Cleanup item_colour slightly more
Simplify using map_find.

It returns a pointer which must be dereferenced to get the value, so
null looking like zero isn't actually a problem.
Add and use a lookup-with-default map template.

As an alternative to map_find for value types.
Simplify
don't leak information about invisible fearmongers
Make polearm brand generation sane (?)

Chance of SPWPN_NORMAL by the time SPWPN_VORPAl was reached was
almost exactly 4/5; (1/5 * 4/5) + (1/5 * 1/5 * 1/6) is roughly
1/6 = 16.6...%, which * 69% (the chance of that brand not being
overriden by a later brand) is roughly 12%.

hooray
also don't leak information about invisible beholders
Small polearm brand correction

Since the odds of getting SPWPN_NORMAL at the SPWPN_VORPAL line
were 3/4ths of what they were for spears, thanks to the SPWPN_
PROTECTION chance...
Fix numeric glyph overrides (#9243)

We had used negative numbers to indicate that the character shouldn't be
mapped through the char_set; but that doesn't work anymore.

In my testing, hex item_glyph overrides seem not to have worked since
0.12 when they were introduced.  mon_glyph was broken more recently.