Remove camera creation from GLGE model driver

It is now created in scene.vwf
refs #2265
Add comment about assumption in navscene.vwf.yaml

refs #2265
Update GLGE apps to initialize camera properties in future call

Temporarily necessary because the camera is not yet created in initialize() - a fix is coming along that will make it so that the camera is created and ready in initialize at which point this madness will no longer be necessary  ;o)
fixes #2265,#2281
Consolidated two "methods" objects in scripting tutorial app

refs #2281