Downloads are left around when moving them across drives

[fuzzyweapon]

If the drive is full, this will actually cause the application to enter an infinite loop.

We need to:

• Make a timeout on the loop
• Detect if the destination is a different drive to delete successfully copied files

[fuzzyweapon]

We don't detect. If a file create event happens and we're going to move it, then we check if the file still exists (and delete it) after trying to move it. If the file was moved, it won't be there to begin with. If the file was copied, then it will be removed.

[fuzzyweapon]

Test Results

• Test got through two resourcepacks (with +s in them) and one mod (skylorlib.jar) and then remained in an infinite loop.
• The files were copied over, as expected.
• The copied files were not deleted.
• Many more jars that were not copied over remained in the Downloads directory

[fuzzyweapon]

So the real issue is with Firefox's implementation. I sloppily added some code to make sure everything got where it is supposed to, but then Firefox leaves around 0KB files in the downloads folder (usually one or two depending on any file events that come in after I've closed the processing loop and finished cleaning up 0KBs).

As it stands, the fix still has stragglers, but I think I should try a short delay between the main action and the cleanup loop.