Fixed imgur album regex

Imgur album regex now handles cases where the user pastes an album link
with trailing information (often found if they have been viewing the
gallery and copy the address bar contents).
Added accidentally omitted character to regex.

The trailing ? was left off the second capturing group, breaking a use
case where an album URL is parsed without any trailing data.
Updated to better Imgur album regex

This regex better handles other types of trailing content in the album
URLs.
Merge pull request #6 from jamesinc/master

Fixed imgur album regex