add move file capabilities

[jneilliii]

• Your changes are not possible to do through a plugin and relevant
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What does this PR do and why is it necessary?

This PR adds a button to the files sidebar that allows for moving a file to a sub folder via modal pop up, and adds new permission MOVE_FILE.

How was it tested? How can it be tested by the reviewer?

Ran it inside development environment and created several nested folders and moved files between the different levels.

Any background context you want to provide?

Feature request on the issue tracker.

What are the relevant tickets if any?

#3596

Screenshots (if appropriate)

Further notes

I'm sure there's some changes you'll want to make. I added some visual cues in the UI if there are any errors when trying to move the file, for example file already exists. Would probably be good to add another comparison to self.enableMove function to handle cases where there are no folders.