Adds getRelatedLinkHrefs
Adds findAllRelated to ResourceRepository
Adds upLink to UsagePoint
Moves constants to LinkType
Refactors MeterReading
Adds related links to MeterReading
Adds setUpResource to MeterReading
Refactors published and updated to GregorianCalendar
Adds convenience constructor
Adds SELF constant
Adds findAllRelated to ResourceService
Extends getResource()
Adds findByUUID to MeterReadingService
wip