* Remove the 'songtitle' field, 'title' can be used instead.
* Remove newlines in the help text, for consistency with other options.
* Add 'from __future__ import unicode_literals'.
* Call '__init__' from the parent class.
* Add test for the format_to_regex method
We need a proper lexer to be able to understand YouTube's code, which contains /* inside of strings.
For now it's sufficient to just disable comment support altogether.
Fixes#4976, fixes#4979, fixes#4980, fixes#4981, fixes#4982.
Closes#4977.