port the most basic suzanne xml3d example to dev2. sceneparser was already ported earlier

this is just the entry point for the standalone example, following how physics2 was created as a new entrypoint previously. notably this is the first entrypoint which works in dev2 without login ui or server connection.

NOTE: free cam does not work here yet, to be improved (possibly the cam from xml3d decl is activated but that one doesn't have controls)