Fixed #12427 -- Started the deprecation path for cmemcache support. Thanks to otherjacob for his work on this issue.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12754 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/core/cache/backends/memcached.py

@@ -7,6 +7,11 @@ from django.utils.encoding import smart_unicode, smart_str
 
 try:
     import cmemcache as memcache
+    import warnings
+    warnings.warn(
+        "Support for the 'cmemcache' library has been deprecated. Please use python-memcached instead.",
+        PendingDeprecationWarning
+    )
 except ImportError:
     try:
         import memcache