Bumping to Houdini Version: 13.0.481
Houdini Engine Version: 1.7 (API: 24)
Create the Asset object when Maya duplicates the AssetNode

Also push all the parameter values to Houdini.
Fix a crash when getting the multiparm size, but the asset is not valid
Reliably check whether the AssetNode was loaded from file or not
Mark the attribute as dirty only if it belongs to a parameter

Previously, asset parameters are not restored properly if some non-asset
attributes were modified.