Added context processor for login URL, added login URL to base template, added embedded discovery service page.

Fixed problem with SPInfo and SPPrivacy URLS. Also changed name of /events/ view to 'home-events' so the 'home' view will point to the one that is actually public.

Removed 'Alpha' from the GraceDB homepage. Also added service provider privacy and info pages, which are required for federation with InCommon.

Added some features to gstlalcbc_report (semi-adaptive mass bins, default query, end_time template filter). Also refactored gstlalcbc_report into reports.py. Some other cleaning up.

To accomodate the fact that our Apache can't do Shibboleth *and* X.509
auth on the same URL and we want both kinds of auth available for the API.

cli_tag, non-functional form drop-down, show tags on event detail page.

New model, EventLog.
Altered event "view" view and event_detail template to show log messages.