MB-10057: stop trying to report checkpoint error messages

Change-Id: If234128166d574573ef3df110c2f5fc098516163
Reviewed-on: http://review.couchbase.org/34041
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
MB-10057: propagate checkpointing errors slightly better

Particularly, propagate real reason of failure rather than useless
generic error message.

Change-Id: I423496398c4315f30e4eca0deb14e9f4ac0b6d7d
Reviewed-on: http://review.couchbase.org/34042
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
MB-10057: expose /diag/eval-able API for resetting vbucket uuids

I.e. for testing and diagnostics/troubleshooting.

Change-Id: I7eac55d4f84d8083fec6f68397e18ae3798d7cb8
Reviewed-on: http://review.couchbase.org/34070
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>