Fixed #2791 -- Added __contains__ method (for "a in dict" checks) to MergeDict. Thanks, Ned Batchelder.
Fixed #2791 -- Added __contains__ method (for "a in dict" checks) to MergeDict.
Thanks, Ned Batchelder.


git-svn-id: 4f9f921b081c523744c7bf24d959a0db39629563@3808 bcc190cf-cafb-0310-a4f2-bffc1f526a37

hugs/django,dcramer/django-compositepks,alex/django-old,mitsuhiko/django,sam-tsai/django-old,jamespacileo/django-france,dcramer/django-compositepks,alex/django-old,rawwell/django,skevy/django,jamespacileo/django-france,t11e/django,Instagram/django,bfirsh/django-old,dcramer/django-compositepks,mitsuhiko/django,Smarsh/django,disqus/django-old,Smarsh/django,django-nonrel/django-nonrel,t11e/django,skevy/django,sam-tsai/django-old,hugs/django,django-nonrel/django-nonrel,jamespacileo/django-france,skevy/django,rawwell/django,disqus/django-old,Smarsh/django,django-nonrel/django-nonrel,t11e/django,mitsuhiko/django,hugs/django,bfirsh/django-old,Instagram/django,disqus/django-old,alex/django-old,Instagram/django,bfirsh/django-old,Smarsh/django,sam-tsai/django-old,sam-tsai/django-old,rawwell/django