Group users of same private domain (#243)

* Added Domain Category field and fix store tests

* Add GetAccountByDomain method

* Add Domain Category to authorization claims

* Initial GetAccountWithAuthorizationClaims test cases

* Renamed Private Domain map and index it on saving account

* New Go build tags

* Added NewRegularUser function

* Updated restore to account for primary domain account

Also, added another test case

* Added grouping user of private domains

Also added auxiliary methods for update metadata and domain attributes

* Update http handles get account method and tests

* Fix lint and document another case

* Removed unnecessary log

* Move use cases to method and add flow comments

* Split the new user and existing logic from GetAccountWithAuthorizationClaims

* Review: minor corrections

Co-authored-by: braginini <bangvalo@gmail.com>

management/server/testdata/store.json

@@ -2,6 +2,9 @@
     "Accounts": {
         "bf1c8084-ba50-4ce7-9439-34653001fc3b": {
             "Id": "bf1c8084-ba50-4ce7-9439-34653001fc3b",
+            "Domain": "test.com",
+            "DomainCategory": "private",
+            "IsDomainPrimaryAccount": true,
             "SetupKeys": {
                 "A2C8E62B-38F5-4553-B31E-DD66C696CEBB": {
                     "Key": "A2C8E62B-38F5-4553-B31E-DD66C696CEBB",