Add additional endpoints to ocm-engine

Dashboard UI requires additional functional in OCM engine:

• Enable cors for agent in REST mode
• Include Dto models into gateway-swagger.json
• Get list of created credential definitions
• Get one credential definition
• Get list of credentials using query filters
• Get one credential
• Decline credential
• Delete credential
• Get all received basic messages using query filters
• Delete basic message by id
• Deleting connection by id
• Get list proof request records using query filters
• Delete proof request
• Short Url for offer credential message
• Short Url for request proof message