converge Split APIs with Mixed and Draft
more split_draft methods
BLD-1099: Edit group configurations.
Merge pull request #4424 from edx/anton/edit-group-configurations

Edit group configurations.
Corrected diff between 0K and 0 C
Merge pull request #4482 from edx/markhoeber/documentation/doc-666

Corrected diff between 0K and 0 C
ispublic is in active use by Stanford.
split create_item and create_child out as separate methods
Merge pull request #4488 from edx/christina/ispublic

ispublic is in active use by Stanford.
Merge pull request #4381 from edx/nimisha/split-converge-api

Nimisha/split converge api