db_to_form_package_schema() crashes historical dataset page

[seanh]

If there's an IDatasetForm plugin active with a db_to_form_schema() method based on db_to_form_package_schema(), then viewing historical versions of datasets (e.g. ​http://127.0.0.1:5000/dataset/dasd%402012-08-30T12%3A26%3A18.524191) crashes.

Reason is that revison_id and revision_timestamp need to be added to db_to_form_package_schema(), something like:

schema.update({'revision_id': [validators.ignore_missing, unicode]}) schema.update({'revision_timestamp':

[validators.ignore_missing, unicode]})