FIX tenant -> service in the "external interface" in order to align terms
FIX minor adjustment in the code after tenant implementation
FIX issues raised in code review
FIX identation
Merge pull request #357 from telefonicaid/task/3222_mongo_backend_final_fixes

Multi-tenant final fixes
Merge branch 'feature/322' into task/feature_322_notify_with_tenant
merged with feature/322