Update Animation.c

fix object size when copy slot datas.
Flip timelines for spine-lua, spine-corona, spine-love.
Minor clean up.
Don't clear FFD if before first FFD key in animation.

Didn't make any sense. Any existing FFD should remain until time passes a key.
Merge remote-tracking branch 'origin/master'
Removed test flip timeline.
IK for spine-lua, spine-corona, spine-love.
Minor clean up.
Merge pull request #289 from zhongfq/master

Bugfixes in 64bit system
setSkin docs.
Merge remote-tracking branch 'origin/master'
Fixed spine-lua IK timelines.
Fixed warnings.
Updated spine-c struct definitions to allow for forward declarations.
Merge branch 'master' of https://github.com/EsotericSoftware/spine-runtimes

Conflicts:
	spine-c/src/spine/Animation.c