Fix scene exceptions URL

[cdloh]

URL was pointing to old github.com domain. Pointed towards .io
domain.

[thezoggy]

I can confirm that this should be pulled,

>curl "http://midgetspy.github.com/sb_tvdb_scene_exceptions/exceptions.txt" -I
HTTP/1.1 301 Moved Permanently
Server: GitHub.com
Content-Type: text/html

vs

>curl "http://midgetspy.github.io/sb_tvdb_scene_exceptions/exceptions.txt" -I
HTTP/1.1 200 OK
Server: GitHub.com
Content-Type: text/plain; charset=utf-8