chef_group isn't fully idempotent

[poliva83]

Similar problem to #83 but this time with chef_group lwrp.

On subsequent runs it keeps reporting its removing orgname for this group.

* chef_group[noc] action create
    - update group noc at https://127.0.0.1/organizations/blackberry
    -   remove orgname

[poliva83]

Seems same problem I reported in #92 can affect users to get updated in a group when they don't need to be.

 * chef_group[dev] action create
 - update group dev at https://127.0.0.1/organizations/blackberry
 -   update users from ["eyurchenko", "dev-blackberry"] to ["dev-blackberry", "eyurchenko"]
 -   remove orgname