MB-12655: ensure that per-node config keys have vclock

There is already code (since 3.0.0) that adds those vclocks for brand
new installations. But we need this too for nodes upgraded from 2.x.

Change-Id: Idd96a4756184ff9b1a06930339ea56a077f11f19
Reviewed-on: http://review.couchbase.org/43335
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
MB-12655: move vclock adding to 3.0.1 version config upgrade

Change-Id: If715d43f1eb1a6ab07fc676a321a0a0ec16bce86
Reviewed-on: http://review.couchbase.org/43337
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
corrected config version to 3.0.2 to match reality

Change-Id: If698f6e067511abf1582c039cfddf124b030281e
Reviewed-on: http://review.couchbase.org/43338
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Merge branch 'rel-3.0.0++' into rel-3.0.1

* rel-3.0.0++:
  corrected config version to 3.0.2 to match reality
  MB-12655: move vclock adding to 3.0.1 version config upgrade
  MB-12655: ensure that per-node config keys have vclock

Conflicts:
	src/ns_config_default.erl

Change-Id: Ie9ad456daae41855c0d7817d9556ede4ca00c291