Get disk sink options from disk_sink_opts environment variable.

Change-Id: I8428a0c1db4678fbb0bb367de63756c6683d765d
Reviewed-on: http://review.couchbase.org/37751
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Pass logging-related environment variables to ssl proxy.

Change-Id: I4a6a5e2dfe57a1dc692a14e224d9ea7b2ac1519f
Reviewed-on: http://review.couchbase.org/37752
Tested-by: Aliaksey Artamonau <aliaksiej.artamonau@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>