This is similar to MDL-31437, but with some specifics for moodle.org.

We need a plugin which will:

• Sync cohorts with course groups across all courses
• But only add the user to the course group if they are also enrolled in the course

Example use case:

• Eloy is a core developer, he is enrolled intwo courses English Using Moodle, and Spanish Using Moodle.
• Eloy is a member of two system context Cohorts, 'Core Developers' and 'Moodle HQ'.
• Eloy should be added to core developers and Moodle HQ groups on both the english and spanish course.
• Eloy SHOULD NOT be enrolled into the Thai using moodle course
• When eloy enrols onto the Thai using moodle course, he should be added to the 'Core Developers' and 'Moodle HQ' groups.