Adding missing wikisource namespace per [1] and [2]

[1]: http://lists.wikimedia.org/pipermail/pywikipedia-l/2013-August/008241.html
[2]: http://en.wikisource.org/w/index.php?namespace=114&tagfilter=&title=Special%3ARecentChanges

Change-Id: I8c48b96e0bfe616569aae593300d2baf425d925e