Added command to delete previews generated by the app

[ariselseng]

Needs tests.

[MiningPickaxe]

Hey, just wanted to bump this a bit :)
It seems like this patch no longer works in the latest versions of this app.
I recieve the following error:

In MissingNamedParameter.php line 17:

  Named parameter "fileid" does not have a bound value.

Would be nice if this could work again

[ariselseng]

@MiningPickaxe If you know php I would certainly like some help merging this. Most importantly this needs unit tests so that we can minimize risk maintaining it in the future.

[MiningPickaxe]

@MiningPickaxe If you know php I would certainly like some help merging this. Most importantly this needs unit tests so that we can minimize risk maintaining it in the future.

Sadly I don't :/ I understand just enough of php to do what the command did by hand.

[ariselseng]

@MiningPickaxe I fixed this now. Use at your own risk.