Preserve PropertyChanged attributes

When the option disabled in XML config:

<PropertyChanged CleanAttributes="false" />

then PropertyChanged attributes like DependsOnAttribute, AlsoNotifyForAttribute, DoNotNotifyAttribute etc won't be erased from build and will be available in the runtime. By default these attributes and PropertyChanged dependency removed from compiled version.

When the option used ensure Package dependency doesn't have PrivateAssets=true attribute which required by default because without the option PropertyChanged dependency cleared