plcb-util: remove some unused macros
Only complain about non-completed batch contexts

Contexts which have been fully exhausted won't leak.
Some more safety around the _cntl routines
Add method to return bucket name
Update MANIFEST
Add 'Cluster' interface per "SDK 2.0"
Add observe method
Allow basic vbucket interface

This allows basic inspection of the current bucket config
Add Data::Printer support for Couchbase::Document
Add more observe tests
Skip over CAS if undef
convert.c: don't complain if raw conversion target is not a PV

We can still use SvPOK instead.
Document: formatting fixups
Updated 'memd_basic' example.