Add manipulative option to match CREATE, UPDATE and DELETE FROM queries

By using the `manipulative` option, you can tell the Rspec matcher to
only look for INSERT, UPDATE and DELETE type queries.

Change-Id: I79275a26e9f127e34a37ed6e1cc186326af0e439
Reviewed-on: http://gerrit.causes.com/45145
Reviewed-by: Henric Trotzig <henric.trotzig@brigade.com>
Tested-by: Henric Trotzig <henric.trotzig@brigade.com>