initial 2.3 commit
More prelim code for event annotations.
Fixed v2.3.0a functionality.
Added test page
Fixed installer to properly handle autobahn python module.
Added annotation libraries.
Added kafka startup script and model manager to add new attributes to existing models.
Added metric query editor UI component for adhoc and page graphs.
Added spline,area,stack graph types. Added API for event types.  Event types are stored via django to the db. Merged annotation functionality.
Updated README
Fixed area chart
Updated sample config
Updated version to 2.3.0
Upated README
Upated README
Fixed pie chart tooltip so header matches color.
Fixed pie chart tooltip so header matches color.
Added startup script for anno receiver.
Updated process count to 20 in uwsgi config.
Code cleanup