Add management command monitoring for edxapp

[robrap]

During an attempt to add some code to edx-django-utils for this, a comment was added that describes some potential alternatives that 2U could implement:

• Add monitor_django_management_command openedx/edx-django-utils#482 (comment).

This doesn't seem to be an urgent issue, but it is a blind-spot.

This ticket would be about assessing the various options and choosing and implementing a solution.

Note that this is highly related to making the platform more pluggable in general, or at least it might lead to docs that help others make these decisions or implement in the future.