fix typo - note by Stephen Frost on IRC
bring the example code for the mediawiki plugin more in line with what
we actually use in production, this mostly consists of the "new style" support
for raw data passthrough, but does not fix the actual problem (which is dealing
with url "double" encoding/decoding - or rather the loss of information about
that) yet...
Will fix that and sync up exactly with the production code for MW 1.19 soon...