fixes#11502
previously, the name of the root course outcome group was
'ROOT.' now it's named after the course to reduce user
confusion.
this commit also includes a migration to fix all existing
courses w/ 'ROOT' titled outcome groups.
test plan:
* create a new course;
* create an account-level outcome;
* in the new course, import the account-level outcome by
visiting the outcomes page, clicking the 'find' button,
navigating to the account outcome, and clicking the 'import'
button;
* verify that the pop-up reads, 'import outcome <outcome name>
to group <course name>?
* run the migration and repeat these steps with a previously
created course; verify that the name still displays properly.
Change-Id: I6f26a9f748b3a5127a751fb9667be9e58b1d4664
Reviewed-on: https://gerrit.instructure.com/14825
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Mark Ericksen <marke@instructure.com>