Refs #366: Adds ability for administrators to alter the status of the observership, brings entrada in line with updated observership tables / model / etc.
Refs #366: Adds update sql, observerships menu item, observership notification cron jobs.
Refs #366: Adds ACL entries to installer SQL and upgrade SQL
Fixes to update SQL. Wrong version number in 1606 entrada.sql, wrong syntax in 1613.sql.
Fixes PHP errors on grade book view and edit pages, adds missing active field to assessments table in upgrade SQL.
Fixes bug that threw PHP error when a course group audience didn't exist.
A few minor bug fixes to associated with adding observerships. Refs #423
For some reason clearfix doesn't fix the formatting issues caused by using floats here when it used to.
Merge branch 'develop' into feature-observership-enhancements

Conflicts:
	www-root/setup/install/sql/entrada_auth.sql
	www-root/setup/upgrade/1607/entrada.sql
Updates course enrolment API to only return required values.
Merge branch 'develop' into feature-observership-enhancements

Conflicts:
	www-root/setup/upgrade/1607/entrada.sql
	www-root/setup/upgrade/1615/entrada.sql
Merge pull request #423 from EntradaProject/feature-observership-enhancements

Feature observership enhancements
If no objectives are mapped to all then no select would be show, preventing course specific objectives from being able to be made available. Deals with an edge case where an organization might only map its top level objectives to specific courses.
Added timed release to event keywords.

Also added an indicator while the MeSH keywords search is running. Event keywords can have delayed release like event objectives, and they can be optionally hidden from students altogether.

On the public event page, keywords are not shown for anyone if there is a delayed release that hasn't happened yet. When keywords are hidden from students, if the user's active group is student then they are hidden. Admins and other users still see keywords that are hidden from students.
Fixes pulling event audience by course ID, which didn't consider multiple active audiences attached to a course at one time.
Fixes bugs in the course enrolment section
Fixes bug where the Attach Learning Event button wasn't being displayed again after an attached event was removed form the interface. Also fixes a bug where no searched events were returned if there was only one group attached to the assessment. Refs #392
Removes group color
Adds prevent default to add_period buttons so user isn't bounced to top of page when adding new curriculum periods to a curriculum type.
Merge branch 'develop' into feature-templates