Camera interface for Player plugin

I patched in a Camera interface to the latest git master, and fixed a couple of compatibility issues that existed with the latest git and Player 3.0.2.

Tested the camera code using the new camera.cfg and camera.world files I added, plus the playercam utility.  You should be able to see the walls of the cave, a white floor, grey walls, and a black sky.

This has been sitting in my "half-done" pile for a while, I figured I'd take a few minutes and get it working and make it apply cleanly to the current git master.