Geometries and mixers are now loaded from the server when the application starts. Currently, the geometries and mixers are hardcoded on the server-side, but it should be easy to change that.

I also made the loading panel a bit nicer, with a message below the animation. In the process, I cleaned up the CSS.
Merge branch 'GWT-storage' of ssh://github/Fingerpaint/project-code into GWT-storage

Conflicts:
	fingerpaint/application/src/nl/tue/fingerpaint/client/Fingerpaint.java