exception_tracker: use a default value of exception store that is working across all instances e.g vcsserver and enterprise.

comments: use proper auth user for close PR action.

comments: fix extracing auth_user from the passed in objects. Before if auth_user is empty we could relly on INT or STR passed in

audit-logs: added entries for branch permissions

exception_store: rename .ini option for future

docs: deprecate beaker.cache in docs

svn: use streaming uploads/downloads of files. - before we buffered whole content before uploading/download - this could lead to OOM errors on big files - now instead we stream when PUT/GET are sent from SVN resulting in faster more efficient data transfer

svn: use shared configurable storage for svn_txn_id interception logic.

celery: use exc_tracker to store tasks exceptions for easier debugging.

exc_tracker: allow setting custom store via .ini file - use safer exc read when listing exceptions.