changed model rotation from accumulative axis/angle rotations to fixed
model coordinate system (left-handed) defined by primary and secondary
axis.

animation code may now rotate these axes to rotate the whole model.
no need for book keeping anymore.
correct orientation for rotation by transforming rotation axis into
local coordinate system
animation partly working (forcing GL update after redraw)

next: rendering in separate thread for smooth user interaction
interactive animations (without threading!)
animations have auto-update now.
rotations now work correctly.

dice are rolled over their edge just like real ones.
+ fixed 'double-click' error, i.e. wrong position initialization when
clicking on still rotating die
just comments...
Merge branch 'master' of git@github.com:lettis/Kubix.git