Moodle Extension (initial commit)

Partially implements grades page.
Placeholder code for tag extension.
Placeholder interaction with database.

Change-Id: I705e052c85ebc15199c7598f278d61f399572dc8
Adding database schema and appropriate hook
Grades page now interacts with database
need to add functions on moodle end to get internal ids and grades

Change-Id: I038268d84c042ef98c8ac5b8ac95bf7f37646279
Stylize

Change-Id: Ib68918ab6f809f6b2985210135597eb29eaac70b
Migrate to JSON i18n

Procedure per https://www.mediawiki.org/wiki/Manual:GenerateJsonI18n.php
with shim.

Change-Id: Icfaef3a3bd3428c622f381637444298cce42507a