Lower the cut-off threshold for tag behavior tracking
Misc fixes to the new route stuff
Add --pidfile flag for writing PID to file
Give /jsapi/ a nice HTML view for debugging and testing
Added missing HTML template
Progress on /jsapi/ and plugins (issue #547)
Added plumbing for Activities (issue #547)
Merge
Fixed so there's no explicit subject on new messages.
Undid previous blooper.
Added json output filter.
Started work on leap plugin.

- Uses new plugin structure.
Removed soledad from mailboxes.
Renamed plugin to leap.
Added startup and shutdown to plugin manifests.
Removed sync from mailbox.unparsed.
Moved config fetch to provider.
Provide mailpile config as param to mailboxes.
Moved LeapSession to session.py.

- Removed unused code.
Added mocking tests for leap integration.