Fix the URL encoding as specified in the OPML RadioTime API.

[lootr]

The following search query generates an error in urllib module that only accepts encoded strings $ mopidy & $ mpc search any 'é' KeyError: u'\xe9'

This can be easily reproduced with $ python2 -m 'import("urllib").pathname2url(u"é")'

[kingosticks]

Good catch. Travis failed with a line length error but fixed and merged, thanks.