Incorp review comments

Hi Keith,

I have incorporated some of your review comments and status is as below,
- [x] GET /groups - The JSON returned for a 'Center (type of group)' has "parentId": 0, parentId should be null and so parameter wont be returned

- [x] similarly for staffId,  incase of null it was returing 0, corrected

- [ ] GET /groups?fields=id  Should be able to return partial response as I require using fields=xxx approach, a number of fields however are not added as part of support data parameters for response. Where I should only see id I see the following:

- [x] GET /groups?officeId=3 - results in exception and does not work as it does for clients

- [x] GET /groups?name=Cen - returns no results when expected and doent work as it does for clients 

- [x] GET /groups?levelId=3 added levelId as param

- [x] POST /groups - with empty json request {} results in exception 
	- would expect mandatory fields of 'Group' to be validated (can you please point me to any referance code in the application)
	- staffIdParameterName = "stafftId" misspelt in part of this validation
	- When creating a 'grouping' I would expect to have to pass the details of the 'type of group' [center, JLG-group, village bank etc] but you seem to infer that its either a center or a group (not done yet)

- [x] GroupLevels domain object returned from read side rather than data object like rest of application.
- [x] GroupWritePlatformService - can remove @PreAuthorize security annotations from interface as permissions checked 	in command infrastruture

Thanks
Nayan Ambali