Instantiate assets right after browing the OTL file
Instantiate assets right after browing the OTL file

If the OTL only has one asset, we instantiate that automatically. If the
OTL has more than one asset, then we show a dialog to let the user
choose which one to instantiate.

pokyfudywise/HoudiniEngineForMaya,sideeffects/HoudiniEngineForMaya,sideeffects/HoudiniEngineForMaya,pokyfudywise/HoudiniEngineForMaya,pokyfudywise/HoudiniEngineForMaya,sideeffects/HoudiniEngineForMaya