This tries to fix the problem of the extra message when a tame
golem is completely destroyed (paper or straw golem burned, iron
golem rusted, wood or leather golem rotted) being issued at odd
times. I basically punted on the visibility aspect since the
original logic was strange: you had to be able to see both the
attacker's and defender's spots and at least one of those two
monsters. Now mon-attacks-mon visibility requires that you be
able to see one of the two and if you don't see both, the unseen
one will be referred to as "it". The "may the iron golem rust
in peace" message is independent of that and may be displayed
after "you have a sad feeling", but now that's intentional and
will refer to an unseen pet by name or monster type, not "it".
This needs a lot of testing and hasn't attempted to address
issue #402: only some attacks that should compeletely destroy
a golem actually do so. (So a hit by fire elemental against a
paper golem does, but passive fire counterattack when a paper
golem hits a fire elemental doesn't, nor does a wand of fire
or being hit by Firebrand.)
Fixes#401
bb9df368af