Faceanalyzer

- Added gaze and face pointing vector intersection with planes in space.
- Detect if someone is looking at something defined by a region in space inside a plane.

Added chessboard asset for camera calibration

- Bugfixes
- added a 3d face representation app to illustrate head and gaze estimation in 3D

- Bugfixes

- Bugfixes
- face orientation correction enhanced
- Eye tracking enhanced

- All pygame examples have been transformed into OOpyGame based examples
- Removed all pygame helpers