Add item_rune to the options guide.
Fix the Webtiles monster list (#7332).

last_client_id is a static variable (used to determine the next client
id to assign), it shouldn't be reset for every monster.
Whitespace/brace fixes.
Remove a 402 years old fart joke.

(Purging now unused desc.)
Refactor 'you.religion' checks.

Pull 'you.religion [!=]= FOO' checks into a function: you_worship(FOO).
This change is part of a large plan to clean up religion.
Don't crash when returning to an level with scrying active (#7387)

The player position is (0,0) in this case, while vlos still uses the
location from the last level.  This caused tile_draw_map_cell (called
from level load) to refer to locations far outside the show area.
Rather than forcing you.pos() and vlos to be in sync at this point
during level load (which could e.g. reveal the upper left corner of the
map), we take the easy way out and prevent a player at (0,0) from seeing
anything (outside arena of course).
Pad some ternary operators with spaces on the left

While this is not explicitly mentioned as a rule in coding_conventions,
all examples listed there apply it as well. The dungeon.cc chunk did
overflow max. columns before already, but could still be looked at.
Don't pretend &=~ is a single operator.
Make a cantrip message substantially less confusing

The monster "looks stronger" actually has a meaning in crawl too, and
many players have asked about what it would mean when used as cantrip.
Do not generate hammers unless defined in a vault

This sets their item rarity to 0 and disallows monsters to spawn with a
hammer as weapon. Yiuf was not harmed in the process.

Their weight of 20 has been redistributed to 19 as follows:
- hand axes (+6) which have the exact same stats
- clubs (+5)
- whips (+5)
- flails (+3)

I also considered a mapping like clubs (+10), maces (+5), flails (+3),
whips (+2) instead but ultimately went for hand axes as suitable filler
because of the exact same stats.
Replace 'you.penance' checks with function calls

Replace you.penance[FOO] with player_under_penance[FOO].