Added 3 events for the feeds controller

These allow for hooking in to the create, update and delete events in a
feed.
Created a rudimentary set of classes to use with custom module events

This adds a simple set of classes which allow for sending email
notifications when a feed record is created, updated or deleted.
Integrated the email notification class with the FeedsController

Now, when a feed record is created, updated or deleted, the respective
events are called.
Made corrections to the feed time field in the feed model

It's required in the database, so was set as such in the model. The test
and label were also updated.
Merge branch 'feature/add_module_management_events' into develop