Ano text meta should be stored directly in the claim hierarchy instead of a separate top level collection

[xandrew]

Mostly for performance reasons. Now the get_arguments call does a bunch of point lookups to get all the ano texts for arguments and counters, probably causing most of the slowness.

This can be made mostly transparent for the ano-text component by just changing ids to the full hierarchy path of the text being annotated and making ano text related backend calls understand this.