MDL-47608 cachestore_mongo: fixed unit test error

If you configured your site to run mongo unit tests and had
the mongo extension and backend installed but did not have the
mongo service running you would get a fatal error when running
the unit tests.
That problem has been fixed by checking the mongo test instance
is ready before returning it.
MDL-46518 navigation: site glossaries now expand properly
MDL-47754 install: fix redirect loop
MDL-47735 mod_forum: added 'My profile' -> 'Forum posts' behat test
MDL-47757 events: Fixed doc block and missing string.

The language events were missing the @since tag and
the grade single view report was missing a language
string.
MDL-47739 form: Calendar widget causes unintentional focus and scroll
MDL-47489 core_grades: Adjust weights of extra credit items for Natural
MDL-47503 Grades: Completely remove aggregationsubcats

This setting is not compatible with combinations of aggregation methods
and the ways in which it does and does not work are not documented. It
was voted to remove it completely by the gradebook workshop, so I have
completely removed it and added a warning for all affected courses + restored
backups.
Merge branch 'MDL-47737-master' of git://github.com/FMCorz/moodle
MDL-47736 editor_atto: only save/restore draft when necessary
MDL-47489 core_grades: Adjust weights of extra credit items for Mean
MDL-47489 core_grades: Adjust weights of extra credit items for Simple
MDL-47489 core_grades: Behat tests covering contributions with extra credit
MDL-47760 grades: dim category name if hidden
Merge branch 'MDL-38065-fix-master' of git://github.com/jmarthaler/moodle
MDL-47725 gradereport_user: Only hide grades when they were altered

The method blank_hidden_total_and_adjust_bounds() now checks for more
than just a grade change, and in that cause would hide the grade. We
added a condition to only hide the grade when it effectively changed,
not when its other properties have.
MDL-47675 phpunit: Update unit tests to pass on MSSQL

Unit tests were failing on MSSQL. gc_collect_cycles() was
removed from the phpunit utils.php file to save time in running
the tests, but MSSQL doesn't clean up open files as well as
other databases.

This patch includes the garbage collection for the unit tests
that require it.
Merge branch 'MDL-47725-master' of git://github.com/FMCorz/moodle
Merge branch 'MDL-47736_master' of git://github.com/markn86/moodle
Merge branch 'MDL-47489-master' of git://github.com/FMCorz/moodle