First kinda functional version

##Added:

• Cancel download
• Limit videos to short ones

Version with UI, but unusable, lot of bugs

• Made in 2 days
• Still buggy and not usable yet
• Using PysimpleGuiQt for UI
• Allows downloading multiple songs in parallel
• You can choose what to do when file already downloaded
• Simple progress bars for all threads

First version, not usable tho

• First version, made in one day
• Propably buggy, haven't tested much yet, not that anyone's gonna use it anyway
• Using only command line interface