Remove I3DEngine CryCommon Interface (#567)

Delete:

- I3DEngine
- Missions
- Time of day
- GameEffectsSystem Gem
- ImageProcessing Gem
- SVOGI Gem
- Various other things that don't do anything now that the legacy renderer has been removed.

Code/Sandbox/Editor/EditorViewportWidget.h

@@ -481,10 +481,6 @@ protected:
     OBB m_GroundOBB;
     Vec3 m_GroundOBBPos;
 
-    //-------------------------------------------
-    // Render options.
-    bool m_bRenderStats = true;
-
     // Index of camera objects.
     mutable GUID m_cameraObjectId;
     mutable AZ::EntityId m_viewEntityId;