Port service API to v3 Part 2

This patch contains the changes required to adapt the service
extension and the corresponding unittest to the v3 framework

This also fix the xml/json inconsistance issue in update:
1:add root element 'service' for json format.
2:merge the extended_service.
3:raise HTTPBadRequest instead of HTTPUnprocessableEntity

Partially implements: bp v3-api-extension-versioning
Partially implements: bp v3-api-inconsistencies

Change-Id: I88cfbe69e0bc0351e81a831345f2a36bf63f5f4f
Imported Translations from Transifex

Change-Id: I3f39a3eb723e9d931e11caa4ef611f1c3646c2ae
Merge "Imported Translations from Transifex"
Merge "Port service API to v3 Part 2"