complexanimation now beginning to be suitable for SVQC use

complexanimation now beginning to be suitable for SVQC use

- only set E5_COMPLEXANIMATION flag when required to save a LOT of bandwidth
- don't also send a legacy frame number when using complex animation to save a bit more
- no more support of "anims that start in the future", use a QC think function to handle them
- fix wraparound logic for complex animation (if a model animation is shorter than 30 sec, it won't jerk when playing the same anim for over a minute)

Bandwidth use per update message:
- simple anim: 1 byte
- 1 blends: 5 bytes
- 2 blends: 11 bytes
- 3 blends: 16 bytes
- 4 blends: 21 bytes
- skeletonobject: 4 + 12*bonecount bytes

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@11546 d7cf8633-e32d-0410-b094-e92efae38249
::stable-branch::merge=bfebdee6f90da32974e4305a33ed15c72ad0a5dc