Teacher subject requests

We need to have a page for previewing all subject requests /subject-requests with option to filter by professor and subject.

Additionally, we should have a page on which each professor can manage his/hers subject requests: /subject-requests/{riste.stojanov}.

This page should display a crud table containing only the request for the professor. This page should allow adding/removing and updating of the subject requests. For all of them, the professor field should be the predefined one from the url.