Fixed NASTY bug with internal properties appearing in public revisions
Fixed NASTY bug with internal properties appearing in public revisions

When implementing CBLRevision, I forgot CBL_Revision is semi-mutable
(its body property can be changed) and stored a CBL_Revision in an ivar
without copying it first. This had very bad side effects when the CBL_Pusher
got ahold of the same CBL_Revision and later added internal properties
to it…
The visible bug this caused was spurious 400 errors saving documents.
Fixes #101

pellekrogholt/couchbase-lite-ios,couchbase/couchbase-lite-ios,myDario/couchbase-lite-ios,amco/couchbase-lite-ios,jkingyens/couchbase-lite-ios,couchbase/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,macoscope/couchbase-lite-ios,myDario/couchbase-lite-ios,amco/couchbase-lite-ios,lordkev/couchbase-lite-ios,pegli/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,amco/couchbase-lite-ios,alfared/couchbase-lite-ios,jkingyens/couchbase-lite-ios,tomco/couchbase-lite-ios,alfared/couchbase-lite-ios,couchbase/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,brendand/couchbase-lite-ios,mz2/couchbase-lite-ios,lordkev/couchbase-lite-ios,amco/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,Chavenay/couchbase-lite-ios,evsukov89/couchbase-lite-ios,Chavenay/couchbase-lite-ios,brendand/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,alfared/couchbase-lite-ios,Chavenay/couchbase-lite-ios,amco/couchbase-lite-ios,brendand/couchbase-lite-ios,jkingyens/couchbase-lite-ios,lordkev/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,lordkev/couchbase-lite-ios,pegli/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,brendand/couchbase-lite-ios,tomco/couchbase-lite-ios,couchbase/couchbase-lite-ios,tomco/couchbase-lite-ios,evsukov89/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,brendand/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,gotmyjobs/couchbase-lite-ios,mz2/couchbase-lite-ios,macoscope/couchbase-lite-ios,tomco/couchbase-lite-ios,evsukov89/couchbase-lite-ios,jkingyens/couchbase-lite-ios,macoscope/couchbase-lite-ios,alfared/couchbase-lite-ios,pegli/couchbase-lite-ios,pegli/couchbase-lite-ios,ipmobiletech/couchbase-lite-ios,pellekrogholt/couchbase-lite-ios,amco/couchbase-lite-ios,mz2/couchbase-lite-ios,amco/couchbase-lite-ios,ryuzmukhametov/couchbase-lite-ios,couchbase/couchbase-lite-ios,macoscope/couchbase-lite-ios,couchbase/couchbase-lite-ios,myDario/couchbase-lite-ios