Document that cmemcached has been deprecated
|Reported by:||Daniel Roseman||Owned by:||nobody|
|Cc:||Triage Stage:||Ready for checkin|
|Has patch:||no||Needs documentation:||no|
|Needs tests:||no||Patch needs improvement:||no|
In , support for the cmemcached library was deprecated. But the documentation still recommends its use, and even links to the page which has a big bold 'do not use'. Docs patch attached.