--WIP--
The webapi allows for arbitrary data to be set in extra_data for certain API resources. Currently, all of that information is accessible through the API which is not always desirable.

The change in progress will allow users to specify private extra data which will be abstracted from the publicly api available information.
Change strips any private data (denoted by leading double underscore __) in any resource that contains extra_data before returning it to an API call.
Associated RB change: https://reviews.reviewboard.org/r/7674/