create a rotation function to rotate sprites

This can be made with "core effects". An effect to be applied to sprites called RotateEffect (the same to scale)

this is more fast than PIL.rotate? (benchmark this)

Start by inspecting the existing core effects and the scale effect to understand how effects are applied to sprites. Compare the proposed RotateEffect with PIL.rotate using a benchmark. Done means sprites can be rotated through the core-effects system and the performance comparison is recorded.

Written by the indexing model from the issue text.