add .tagged? command
Merge pull request #99 from tomjakubowski/tagged-command

add .tagged? command
Youtube plugin no longer relies on locale (fixes #53)

The plugin relied on the locale module to provide digit grouping of the view count. It could cause various encoding issues.
The digit grouping is now based on a simple homemade function.
add license (public domain). fixes #100

I don't have CLAs from everyone involved (it's an IRC bot), but almost all
the core code was written by me and should be safe.
metacritic: Resets PSV to VITA, added XONE and PS4, changes score class check from metascore to metascore_w
add requirements.txt, remove pycparser from plugins