Buff draconian knights (a fair bit) and draconian scorchers (mildly)

Despite shifting away from a complete mess of cribbed spellsets,
draconian knights still had a smattering of indistinct spells despite
the vague theme of buffs, ice, and necromancy. They're the only draconian
class that had spellset variation, and they hardly got anything particularly
dramatic like the crystal spears, hellfire, blink allies encircling, or
summon miasma like the other classes. Altogether, this made them not
particularly memorable; despite a bunch of weak unique spells, they were
not any more noticeable than the reavers everywhere else.

Ironically enough, I'm concentrating their spell sets together in a fashion
that makes them a stronger version of those reavers. Their previous spell sets
were:
1. Bolt of Cold, Throw Icicle, Bolt of Draining, Invisibility, Simulacrum
2. Bolt of Cold, Throw Icicle, Lightning Bolt, Vampiric Draining, Agony
3. Bolt of Cold, Throw Icicle, Haste, Animate Dead, Ozocubu's Armour
Their current set is now simply:
Bolt of Cold, Throw Icicle, Haste, Invisibility, Simulacrum, Ozocubu's Armour.
Always having Haste, while hardly unique compared to other places, gives them
an edge compared to other draconians. They've also gotten a free 1/3 chance for
a good_item weapon, which altogether should produce a class distinct for
shredding players to bits by themselves instead of relying on randomness,
blasting, or allies (though they can still cover all three). They're still equal
in arena to monks, somewhat, so it should be fine. It's Zot, anyway.

To move on, draconian scorchers are sad for a relatively simple reason:
they are an explosions-focused, elementally-focused version of the annihilator,
but with the explosions they are rather neutered by simply being as surrounded
or adjacent to the scorcher as is likely with their bands. To slightly fix this
problem up, their sticky flame (which is a weaker copy of a draconian breath,
and no longer significant with item destruction's passing) has been replaced
with Bolt of Magma, so they've got a bit more blasting without collateral
concerns.
Don't crash in potion petition (9168)

Specifically, when retrying to get a potion set containing at
least one cheap-enough choice.

FR: make this not bad
Fix hydra form transform message

Always claimed "you turn into a 1-headed hydra";  was broken by
99fa9bcd.
Re-allow vp butchering for everyone

Why not?
Simplify (bottling code)
Consider AF_FIREBRAND as a source of fire for Dithmenos.
Fix wellspring cast message.
Revert "Webtiles: scale dungeon canvas by devicePixelRatio." (#9189)

This has unintended side effects at present, so this shouldn't go live
until I figure them out.

This reverts commit 75d9865c86980b792806e6248855cba6e09b9c1a.
Fixed crash in dgn-delve.cc for too-small maps
Moved delve layouts to their own file
Add 2 more delve-based layouts.

[Committer's note: this also squashes in the update to
layout_twisted_circle.]
Don't try to place Storm card clouds on open sea.

And let them place over a few more features.
cap stress tests at 8 minutes

travis will forcibly terminate the test after 10 minutes with no output,
so we should kill the process before that happens so that we actually
get a crash dump
place the player before the statue in the fireworks test

otherwise, the player might randomly already be at (40, 40), and so
placing the statue might fail
Remove another unused item prop.
Make clua food.can_eat() not crash on non-food items (HDA)
Tell Lua that skeletons can't be bottled (PleasingFungus).
Fix some formatting

Most of this is util/checkwhite and util/unbrace, with some corrections
were those scripts reformatted the code incorrectly.
Add a comment about a parallel enum and array.
Add base monsters for zombies spawning in early D (theTower)

If a zombie placed on D:1-3, it was possible the zombie spawn list
wouldn't be used because there were no eligible options.