Allow Gigas to perform all his attacks

The only one disabled for now is the thunder blast, not enough stable imo.

Also, there is a problem with Gigas actually but the bug seems to be from
the engine.
Fixed a bug in sprite of Gigas

The hands down animation was out of bound.
Clean Gigas and fix problem with his timers

He had no optimization distance set so when going out of screen, timers
was interrupted, making balls never remerge.
Merge branch 'develop'