Merge branch 'gcp-anthos' into 'master'

NOTICE

pom.xml

provider/register-reference/README.md

provider/register-reference/pom.xml

...ster/provider/reference/ReferenceRegisterApplication.java

.../provider/reference/action/ReferenceActionRepository.java

...ster/provider/reference/ddms/ReferenceDdmsRepository.java

...osdu/register/provider/reference/mapper/ActionMapper.java

...p/osdu/register/provider/reference/mapper/DdmsMapper.java

...egister/provider/reference/mapper/SubscriptionMapper.java

...r/provider/reference/model/MongoRegisteredInterfaces.java

...ter/provider/reference/model/document/ActionDocument.java

...ister/provider/reference/model/document/DdmsDocument.java

...ovider/reference/model/document/SubscriptionDocument.java

.../reference/repository/mongo/ActionDocumentRepository.java

...er/reference/repository/mongo/DdmsDocumentRepository.java

...ence/repository/mongo/SubscriptionDocumentRepository.java

.../provider/reference/security/ReferenceSecurityConfig.java

...ister/provider/reference/subscriber/PushSubscription.java

...reference/subscriber/ReferenceSubscriptionRepository.java