Evoke fog ability icon for cloak of the Thief (Reaver)

Taken from <https://crawl.develz.org/mantis/view.php?id=6896>.

(cherry picked from commit 32e5fa84aeeb3db323bdeaab22ee64f00e3092e8)
Assert-crash on invalid zaps.

This means battlesphere with zap-less spells will crash every time instead
of an elusive crash on only some builds, as almost always this invalid
memory access happens to be within our space.

(cherry picked from commit ecbae3b9e75e7bb180f2abd9f5583162d4b3f86e)
Fix a battlesphere crash with non-standard zaps, improve tracing of bouncy beams

If the spell triggering battlesphere does not use a standard zap (ie: dazzling
spray, mephitic cloud, probably some others), fall back to tracing the path
as if magic dart was being cast. (This would otherwise crash consistently now that
an assert has been added for it)

Also fix broken code for tracing the path of bouncing beams. Previously only the
part up to first wall impact would be traced, meaning that if the monster you
were aiming for would only be hit after a bounce, the battlesphere would not lock
onto it.

(cherry picked from commit b433f32bc8aeee9192c2a2c94ae9ad2046874440)
Changelog for 0.12.1
Fix a crash with aiming magic dart past monsters with a battlesphere out
(cherry picked from commit d4d2116d3a34cc14cdef3279f68fdc30bb70bbf0)
Mention cursed blunt butchery in the changelog.
s/dazzling sphere/dazzling spray/ in the changelog.
Merge remote-tracking branch 'upstream/stone_soup-0.12' into gettextized-0.12
0.12.1 버전적용.

Conflicts:
	crawl-ref/docs/changelog.txt