Fixes and formatting for README.md

Change-Id: I80939e69ab7cfef063461386107ccbc82df8f76e
Reviewed-on: http://review.couchbase.org/26294
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>