MDL-47975 assign: Stop gap fix for random time fails.
MDL-30968 mod/forum Fixed group link
MDL-39376 enrol: Optimized setting for ldap and database
MDL-48156 task: Skip the scheduled task only for really disabled plugins
MDL-48093 HTML 5 video: Firefox now supports .mp4
MDL-48144 upgrade: add v2.8.0 sep lines
MDL-48168 quiz editing: max grade should be editable after attempts

Note that there was a lot of legacy code left from Moodle 2.7 which is
no longer required, and I took this opportunity to delete it.
Merge branch 'MDL-48144' of git://github.com/stronk7/moodle
Merge branch 'MDL-48156-master-pluginisenabled' of git://github.com/mudrd8mz/moodle
Merge branch 'MDL-39376-master' of git://github.com/FMCorz/moodle
Merge branch 'MDL-48168' of git://github.com/timhunt/moodle
Merge branch 'MDL-48093-master' of https://github.com/sammarshallou/moodle
Merge branch 'MDL-47975-master' of git://github.com/damyon/moodle
MDL-47502 test_statslib_cron_daily: fix provider

Fiddling with the database in the data provider causes "out of sync"
errors when running suite tests.
MDL-47502 statslib tests: improve test

While integrating I noticed some problems which already existed in this
test:
* The enrolment data generator was not used
* The student roleid was hardocded
* The role assignment was at site level..
Merge branch 'MDL-30968-master-forum-group-link' of https://github.com/amandadoughty/moodle