re-enabled OGRE in OpenCS; cleaned up startup
added navigation mode enum to SceneWidget
moving the camera with W and S keys
use shift key to speed up camera movement
moving the camera with A and D keys
mouse wheel zooming
camera panning via left button drag
getting rid of some magic numbers
camera rotation via ctrl-left button drag
fixed mouse button release detection
inverted ctrl key
added navigation mode selection
added navigation class
moved implementation of the 1st person camera into a separate file
added free navigation mode
rolling
keep camera upright in 1st person mode
added orbit navigation mode
Merge remote-tracking branch 'upstream/master'