Don't call mochiweb_util:parse_qs/1 with an undefined argument.
Don't call mochiweb_util:parse_qs/1 with an undefined argument.

Found this while debugging COUCHDB-1116.

Closes COUCHDB-1116

git-svn-id: c1f8a8ec0b3bb2e99ab3413722f81f687760e79c@1094034 13f79535-47bb-0310-9956-ffa450edef68

alanning/couchdb-couch,ngpestelos/couchdb-couch,alanning/couchdb-couch,fkaempfer/couchdb,KlausTrainer/couchdb-couch,fkaempfer/couchdb,KlausTrainer/couchdb-couch,fkaempfer/couchdb,ngpestelos/couchdb-couch,cloudant/couchdb-couch,apache/couchdb-couch,alanning/couchdb-couch,fkaempfer/couchdb,smithsz/couchdb-couch,fkaempfer/couchdb,fkaempfer/couchdb,KlausTrainer/couchdb-couch,apache/couchdb-couch,smithsz/couchdb-couch,cloudant/couchdb-couch,smithsz/couchdb-couch,apache/couchdb-couch,cloudant/couchdb-couch,ngpestelos/couchdb-couch