Fix slashes in filename and flip title/artist order

If there was a / in the title, it would think that it was a
subdirectory and make the zip file weird.
Comments editable/deletable for 1 hour
Hearts instead of like counter
Cannot like own songs, plus more anonymity

Everything on your screen looks the same whether or not you are the
mixtape owner, except for the fact that the buttons don't work.
Link to comments
Add download all

This will need some refactoring when I have time.
Add download to mixtape page
Add better comment numbers