Overgrowth alpha 51

Here is what is new in Overgrowth in this weekly alpha. If you are confused what a weekly alpha is, or even what Overgrowth is, please read our fancy FAQ. Basically, we are developing a massive video game from the ground up -- we are able to do this completely independently by accepting preorders for the game before it's done!

Here are a few highlights from the source repository:

- Mousewheel twist controls for animation editor
- Better forward kinematics
- Animation editor resize
- Pose flip command (ctrl-x)
- Hooked up alt-drag keyframe copy
- Animation saving/loading
- Escape key exits rabbot mode
- More work on undo/redo
- Rearranged ribbon
- Neat new main menu
- Cleaned up and added some levels
- Implemented masks for UI windows
- Double clicking places keyframes
- Alt-drag to duplicate keyframes
- Initial UI resizing
- Fixed ribbon toggles
- Bug fixes

Thanks as always for all the support! See you guys in IRC and the forums.