Fleshed out the readme.
Updated the pom file to generate the javadoc
Added javadoc to Datatree. Removed a dead type.
Added javadoc for the io.rdf package
Merge branch 'feature/documentation010' of https://github.com/drdozer/sbol-data into feature/documentation010
Removed the self enclosing br tags
Added a lot of javadoc.

Fixed a couple of minor API visibility, signature and name issues on the way.
Merge branch 'feature/documentation010' of github.com:drdozer/sbol-data into feature/documentation010
Updated uses of NamespaceBinding to fix all uses of the constructor that's now hidden.
The javadoc for RDF io now make it through javadoc 8.
Added package docs for datatree.
Now building source and javadoc jars.
Added documentation for the sbol-example project
All done with the pom for now.
Removed the ability to add properties to a DocumentRoot.

This allowed us to remove the property type parameters from all over. We could also add name type parameters to the literals. The resulting APIs are vastly cleaner and there are fewer magical casts.
Merge branch 'feature/documentation010' of github.com:drdozer/sbol-data into feature/documentation010
Merged and fixed javadoc
Added uml diagrams for sbol2.
Merge branch 'feature/documentation010' into develop