Puller was getting confused receiving JSON-only docs (no attachments) with gzip response encoding
Puller was getting confused receiving JSON-only docs (no attachments) with gzip response encoding

It was looking at the “Content-Encoding: gzip” header and thinking that this was a JSON _part_ that
was encoded, so it tried to decode it itself. Whereas the top-level gzip decoding is done already by
NSURLConnection. So it was trying to gzip-decode plaintext, oops.
Fixes #281

amco/couchbase-lite-ios,macoscope/couchbase-lite-ios,tomco/couchbase-lite-ios,tomco/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,pegli/couchbase-lite-ios,mz2/couchbase-lite-ios,couchbase/couchbase-lite-ios,Chavenay/couchbase-lite-ios,amco/couchbase-lite-ios,amco/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,alfared/couchbase-lite-ios,couchbase/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,pegli/couchbase-lite-ios,couchbase/couchbase-lite-ios,jkingyens/couchbase-lite-ios,Chavenay/couchbase-lite-ios,brendand/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,brendand/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,brendand/couchbase-lite-ios,pegli/couchbase-lite-ios,macoscope/couchbase-lite-ios,pegli/couchbase-lite-ios,tomco/couchbase-lite-ios,alfared/couchbase-lite-ios,alfared/couchbase-lite-ios,jkingyens/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,lordkev/couchbase-lite-ios,alfared/couchbase-lite-ios,couchbase/couchbase-lite-ios,Chavenay/couchbase-lite-ios,brendand/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,mz2/couchbase-lite-ios,amco/couchbase-lite-ios,macoscope/couchbase-lite-ios,amco/couchbase-lite-ios,jkingyens/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,brendand/couchbase-lite-ios,amco/couchbase-lite-ios,lordkev/couchbase-lite-ios,tomco/couchbase-lite-ios,couchbase/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,jkingyens/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,lordkev/couchbase-lite-ios,mz2/couchbase-lite-ios,lordkev/couchbase-lite-ios,macoscope/couchbase-lite-ios,amco/couchbase-lite-ios,couchbase/couchbase-lite-ios