Breaths can no longer be reflected (except disintegration)

Reflection still works against wands and spells, and disintegration
breath specifically in the interest of fairness.  This is the first step
towards differentiating late game characters by making resistances
relevant beyond the Castle.
Enable hit bonuses for martial arts/bare-handed combat

NetHack has always had code to calculate the to-hit bonus for unarmed
combat, but never ran it due to faulty logic, which this commit fixes.

From SporkHack r140 and r188.
Make 1-damage hits still train weapon/unarmed skills

In NetHack, hits that do 1 damage will not train the relevant weapon or
unarmed skill, making low damage combat options (e.g. knives, pick-axes
and unarmed combat/martial arts) harder to train than higher damage ones
(e.g. long swords, sabers).

This commit trains weapon/unarmed skills on successful hits regardless
of damage, making it easier to train all skills, especially low damage
ones.
Accelerate training of heavyshot skills

Firing and hitting with 3 arrows trains the bow skill 3 times, but a
heavyshot crossbow bolt that did 3 times damage only trained the
crossbow skill once.  This amends the latter case, though using the max
heavyshot bonus instead of the 1d(max) used to multiply damage.
Fix losehp() type signature for killer_format type

k_format should definitely be an int, not a boolean, especially since
losehp() was being fed with very not-boolean values.
Fix crash when positioning revived monster on level entry

The place_monster() call from montraits() was failing due to the
newly-created monster's dlevel field not being set.

Bug discovered by Deathkiss.

This bug also exists in upstream NitroHack.
Eat/crowning-gained intrinsics provide only partial resistance

Intrinsics gained from eating corpses, eating jewelry as a monster and
crowning now only provide partial protection:

 * fire/cold/shock: half damage
 * sleep: half duration, doubled chance to awaken from combat
 * disintegration: 90% chance to nullify disintegration
 * poison: half damage, having any protects against other effects

Intrinsics gained by race or role and extrinsics from worn equipment
provide full immunity to these special attacks.

Other changes:

 * free action provides sleep immunity beyond potions of sleeping
 * gremlins can no longer steal race/role-acquired intrinsics

Based on Leon "L" Arnott's resistance patch.

 * http://l.j-factor.com/nethack/resist.diff
 * http://bilious.alt.org/?298
Display non-reflectable breaths differently to reflectable beams

All breaths that cannot be reflected (i.e. everything except
disintegration) display as asterisks instead of lines.

Also, fix size of zapsyms array in drawing.c.