CBD-688: cli spec to support 2.0 features

Revise based on func spec review

Change-Id: Ifeb9f518f88db603a5b0229443748e97acac361a
Reviewed-on: http://review.couchbase.org/24611
Reviewed-by: Bin Cui <bin.cui@gmail.com>
Tested-by: Bin Cui <bin.cui@gmail.com>