Repository API query signatures Entity free (#403)

* Migrated target management queries to IDs inetsead of full entities

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Added missing comment.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* refactored target,DS,cont,deploy,rg mangement.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Adde versioning documentation.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Rollout, Dist and Software mgmt refactored

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Readded line that was remove by incident. 

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Fixed broken tests.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Query management refactored

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Fix bug of auto assign DS delete

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Switch to collection

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Fixed compile error

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Small glitches

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Fixed test after merge

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

hawkbit-mgmt-api/README.md

@@ -1,7 +1,10 @@
-# Eclipse.IoT hawkBit - Mgmt API 
+# Eclipse.IoT hawkBit - Management API - Model and Resources
 
 This Management (Mgmt) API is used to manage and monitor the HawkBit Update Server via HTTP. This API allows Create/Read/Update/Delete operations for provisioning targets (i.e. devices) and repository content (i.e. software).
 
+# Version 1
+
+The model follows [semantic versioning](http://semver.org) with MAJOR version, i.e. breaking changes will result in a new MAJOR version.
 
 # Compile