Move video thumbnails to VideoThumbnails/, fix video renaming not renaming the thumbnail as well

Play sndFirstBlood after first damage/kill/poisoning of enemy (instead of ANY damage) This avoids sndFirstBlood being played for self-harm, for which this taunt is a bit odd.

Don't play "LeaveMeAlone" taunt if attacker hits same hog multiple times in same turn Because weapons like cluster bomb could trigger it in a single turn otherwise. The idea is the same hog must be hit across multiple turns.