Buff deep elf knights (new spell sets, more damage)

Once more, a reaver with a mess of spells is cleaned up a little,
though this time multiple spellsets are definitely kept. The deep
elf knight was little more than a stronger deep elf fighter, which
is already a differently-equipped differently-placed orc wizard.
To emphasize the vague melee prowess suggested by the name "knight",
they get a 1.5x base damage boost from 14 to 21, making them not weaker
than orc warriors. They're also getting new spell sets, with a mix
of conjurations and self-buffs. The original three spellsets they had
were directly from orc wizards:
1. Magic Dart, Slow, Haste, Blink
2. Throw Flame, Invisibility, Magic Dart, Confuse
3. Throw Frost, Cantrip, Haste, Throw Flame, Magic Dart, Invisibility
Their new spellsets, emphasizing some sparsely-used spells and a bit
more sheer strength:
1. Dazzling Spray, Conjure Flame, Invisibility, Swiftness
2. Throw Icicle, Haste, Invisibility, Condensation Shield
3. Stone Arrow, Iskenderun's Mystic Blast, Haste, Shroud of Golubria

Nearly all of the placements of deep elf knights have been left
untouched; its use as a strong mid-tier elf should make more sense
now. The only exception is possibly the earliest one, in one of the
baileys: there, the equipment has been deliberately held back to
essentially nerf its use there.
Make revenant abilities natural, not spells

"A skeletal form wreathed in cold blue fire, standing astride this life and
the next. Echoes of the lingering dead flicker within its ghostly flames."

Nothing about their description or the overall concept suggests spellcaster.
As such, they're now natural abilities. A minor antimagic hit (it's still
good for some other Crypt / Tomb monsters), and more importantly also means
they can work under silence, as is relevant with either silent spectres
or as such the only un-impaired serious casters in Tomb.
Remove did_god_conduct's return value

Over sixty+ calls, it seems to have been used in exactly one
place, and I'm pretty sure that was irrelevant now that weapons
auto-id when held.

Also refactor a scrap of Zin conduct code, since I was passing
through.
Make revenants magically delicious (wheals, theTower)

AM=Y, Sil=N.
Statically initialize a map.

Hooray for C++11!
Move an enum

Since it was used very narrowly, there was no need for it to live
in enum.h.
Simplify noise in melee attacks

The old, complicated, spoilery, way was effectively never relevant. Now
only damage, if the attack is a stab, and the Noise property on randarts
are considered.
Tutorial & hints: spell success rate -> spell failure rate.
Remove an unused parameter from discover_mimic.
Don't discover mimics using Ash/antennae detection.

This takes away the whole point of a mimic, which is that it presents
a surprise when you find that it is not actually a real item/feature.
Instead, you go down some stairs, or have a new square come into view,
notice a square of smoke, glance down at the message log, and say "Huh,
there was a mimic of something somewhere."
Remove an unused function.
Fix a mistake in rebasing.
Remove some unused ABFLAG_s.
Mindexicide: MiscastEffect.

I also cleared out what appeared to be dead code while I was there,
though I may have missed some logical errors, especially with blaming
(for gods etc.). This includes removing MiscastEffect::guilty; it was
used very haphazardly, sometimes being surrounded by uses of act_source,
and I'm not sure that it was ever different.
Remove {target,source}_as_monster.

This will cause a segfault if target is NULL, but it already would
if the result were dereferenced if target were NULL or &you.
Fix typo
Remove two levels of indentation
Remove an unused argument
Reorder one shout database entry

To match the order everything else is in.
Remove irritating high-pitched whines

This has been unused since the blowfly removal of 0.8.0-a0-4860-g7bcc156
- mosquitos have buzzed since that commit as well. By now the addition of
new whiny monsters seems rather unlikely.

[ wheals: Fix compilation. ]