Fix for local mode

This fixes --local mode, which broke because files was never defined.

Dual mode is here!

Update 1.4.1 brings dual mode!

Dual mode lets you keep your local copy of clips when upload to Google Drive, by setting the -d/--dual flag!
This also makes sure that clips that were already present when the tool was started are not overwritten or deleted, even without dual mode on!
When you forget to set the dual flag, your already downloaded clips will survive!

Huge convenience update!

Update 1.4.0 brings multiple new features, as well as some fixes!

Additions:

• The GPL-3.0 License
• Filtering clip titles via regular expressions
• Filtering clips in multiple categories at once
• Filtering clips from multiple clippers at once
• Downloading clips from multiple streamers at once

Fixes:

• When a clip download is interrupted, the partially downloaded clip is now deleted from your drive
  This makes sure it is not skipped when running the tool again
• Various spelling mistakes, etc.

Minor stuff:

• Replaced my donation link with a cooler, non-custodial tip jar

Bring back .mp4

At some point, the .mp4 file extension for the downloaded clips apparently got lost! This patch fixes that.

Edit: Maybe they were never there and I just didn't notice lol

Windows hotfix

This patch fixes a bug that caused the tool to not find necessary files

The Category Filter Release!

You can now filter clips by category with the --category option!

The Windows release!

The utility now detects if you're running Windows and will adjust the file names accordingly, removing any reserved characters.

v1.1.0 - Filter clips by clip creator!

This release allows you the option to download only clips created by a person specified via their twitch username by using the --clipper flag!

Initial release

This is the initial release of the utility.
All basic features should work.