Episode 0 : - Camera on player -
+ Refactored : CAMERA interface
+ Added : ZELDA_CAMERA centered on the player0
+ Added : KeyboardCB & UpdateCB to CAMERAs (resp.  @ controller update end & @ renderer update begining)
+ Added : Math macro for angle conversion, PI...
+ Added : QUAT : Conjugate, Hamilton product
+ Added : QUAT : static vector rotation with angle/axis (through Hamilton product (slow) or neat derivation found on the intraweb)
+ Cleaned : Actor inline fcts
+ Cleaned : World inline fcts