Improve log messages to account for what's seen, etc.

Pull damage_types.lua's logic to handle this into new Actor methods
getLogName, getSrcName, getTargetName, and use them in Combat.lua also.

Add game.logSeen2 (taking 2 entities) and make sure that combat log
messages are shown if either participant is visible.

Cosmetic iprovements: Tweak blindsense's appearance. Better redraw FOV
if talents change it.