20130110

- Initial work on camera override implementation (type8).
 - Highly experimental, minimal implementation.
 - Cameras have to be assigned to passes, like other entities.
- Scene parser code looks peculiar - reviewing.
 - Need to investigate to see if it's still ~correct.
 - It seemed to leave files hanging open, which is odd. Revised code to
ensure input files are closed. Can revert if something breaks.
 - Added functions for the camera handling.
 - Adjusted end line function operation to be more generic. May need
more careful thought - haven't investigated third party light/camera
handling yet. Anticipating that this change might need to be reverted.
- Refined UI code for the renderer selection dialog for the scene
master override (creation).
- p0016 still lurking.
- p0019 created
- p0020 created.