CCBC-549: cbc: handle cbcrc options better

- Pass username to lcb
- If configuration file parsing fails, exit instead of warn

Change-Id: I4cf2ec4fb09fc24029ac2dbb729ce0f3c332d320
Reviewed-on: http://review.couchbase.org/43286
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>