Improve deletion system

[simplyboo6]

The deletion system is a little bit odd. When files are deleted they're added to a media.deleted collection and the source file is also removed. They're then ignored if found again.

Ideally this needs some improvements:

• A screen for seeing the paths of deleted media or during import having it included as a list of ignored things that has an X allowing you to remove if from the ignore list.
• In the delete modal deleting the source file should be optional, preferably defaulting to false. This is the only place in the application that source files are modified. It's inconsistent especially without warning.