grilo: Remove fixed FIXME
grilo: Add Tracker to search

It supports search, and we were skipping it.
grilo: Call Tracker "Local" in search
grilo: Guess episode metadata for local files
grilo: Fix a bunch of compile warnings
backend: Unlink the Go and Volume buttons

As advised by Jakub Steiner.
grilo: Split adding to the tree views

To allow us to add from the content-changed signal.
grilo: Fix memory leak of the mtime
grilo: Fix crasher when exiting when loading icons
grilo: Add update_media() function

Modelled after add_media_to_model()
grilo: Monitor source contents

We support add/remove/changed events for "Recent" view, and
changed/delete events for the other view.