MultiCam

• Fixed some issues with the scissor test
• Jump and Sneak now make the camera rise or lower
• Added the ability to disable rendering of entities, block entities and particles
• add /multicam orbit command for orbiting a fixed point
• Holding Sprint now makes you move twice as fast
• Added /multicam move and /multicam zoom commands for moving cameras and controlling their FOV
• Actually set the window's icon

Initial release.