extracting out the bulk record media type, splitting 'CollectionCoverage' into 'Coverage' and 'CollectionContent'
refactoring 'RecordSet' per architecture discussion
finishing up the accommodations for the bulk record media type
Merge branch 'master' into bulk-records

Conflicts:
	gedcomx-model/src/main/java/org/gedcomx/Gedcomx.java
	gedcomx-model/src/main/java/org/gedcomx/conclusion/Person.java
	gedcomx-model/src/main/java/org/gedcomx/records/Collection.java
	gedcomx-model/src/main/java/org/gedcomx/records/CollectionCoverage.java
	gedcomx-model/src/main/java/org/gedcomx/records/Record.java
	gedcomx-rt-support/src/main/java/org/gedcomx/rt/GedcomxConstants.java