Feature/nta restapi

Created new REST API module and updated the POM.xml and nta-dist.pom.xml
Added new API classes(Root, Tracer and Transaction)
Added new service classes (Transaction and TraceLogging)
Added new Exception Handlers that implements ExceptionMappers
Added a LinkBuilder class to provide the correct url for collections within entities.
Added hibernate validation on the requests for the api.
Added Response Classes create well formed responses from the REST API.

This feature is still a work in progress. However, I would like the current work to be reviewed before moving on to the Participant and Event API classes. In addition, each of the API and Service classes will require unit tests.