Analyze a way to implement signal handling without modifying base platform

[fsologureng]

EOL modifications here should be done in eol_forum_notifications repository:
https://github.com/eol-uchile/edx-platform/blame/66a7029ea9ab48f42b71ccd462f2cb2d69df8b04/lms/djangoapps/discussion/signals/handlers.py#L79