Update patch set 4

Patch Set 4:

> Looks like pymemcache does not support the binary protocol, so does
 > not support sasl.  (there's another issue for missing ipv6 support)
 > 
 > pinterest/pymemcache#54
 > 
 > looks like this is required for sasl support, sadly  In
 > global-requirements, do you mind adding a comment above the entry
 > stating that it is only required for sasl/binary protocol (so that
 > it can be cleaned up if/when sasl/binary protocol is merged into
 > another 'approved' library).

I think this is the best option we can think for the current situation.

Patch-set: 4
Reviewer: Gerrit User 31827 <31827@4a232e18-c5a9-48ee-94c0-e04e7cca6543>
Label: Verified=0