[manialinks] Basic animations for server-side manialinks!

[reaby]

For some time i'v been missing little eye-candy for server-side manialinks... Basic animations!
in really basic level this would be fade in / out --> opacity change, and from-to position move. for more advantage level it maybe would have rotation and scale. With these it could be possible to create some eye-candy to user. Created windows could then just appear by fade to user and go away with fade etc etc.

[fastforza]

Depending on how ManiaScript will work, we might be able to bind animation events to manialink elements. It would be really cool to accomplish this.