Add serialVersionUID.

Add serialVersionUID to entity classes.
Add Guava dependency

Add Guava 15.0 dependency to API. Guava includes a great set of
Collections classes.
Return repository list as JSON

Add a controller in /rest/repositories for returning repositories info
group by serviceType in JSON format.
Pull Remote instance info from server

Populate Catalog Of Services, Name OGP Repository and Data Repository
with actual data from /rest/repositories service.
Merge pull request #13 from juanluisrp/catalog-of-services

Catalog of services from server