Add Quota management feature to the client with unit tests

1. Implemented quota operations like below:
```
ORG ADMIN:
   quotas                             List available usage quotas
   quota                              Show quota info
   set-quota                          Assign a quota to an org

   create-quota                       Define a new resource quota
   delete-quota                       Delete a quota
   update-quota                       Update an existing resource quota
```
2. Get quota from org as embedded resource.
3. Throw FORBIDDEN exception if quota operation is not permitted.