properly remove users from instructor/staff groups on a course delete
STUD-1555
Merge pull request #3304 from edx/zub/story/deletecoursegroups

properly remove users from instructor/staff groups on a course delete
Set initial video quality to large instead of default to avoid automatic switch to HD when iframe resizes. [BLD 981]
Separate each problem type into its own file

Separate all exercise and tool types, and create a new folder to contain them.
Merge pull request #3360 from edx/DOC-224

Doc 224
Merge pull request #3447 from edx/jmclaus/bugfix_hd_button_activates_by_itself

Set initial video quality to large instead of default to avoid automatic switch to HD when iframe resizes. [BLD 981]
Typo corrections
Merge pull request #3453 from edx/sylvia/docs/DOC-224

Typo corrections
DOC-115 adds topics to make data interpretation easier
Merge pull request #3287 from edx/ahodges/documentation/DOC115

Ahodges/documentation/doc115
Configure youtube stub for bok-choy
x
configs
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