Comment unused code:
    - checkSSS and checkSceneLights is moved to integrator export panels.
    - deactivate render buttons operators code. Blender buttons is used now.
    - 'lock camera to view' render option is used now, instead 'use 3dview'
Comment unused 'useViewToRender' camera specific code:
    - now, you can use 'lock camera view' Blender option.