Added SWE Common StaX parser, now passing all tests
Fixed error in O&M test XML file
Added my own IndentingXMLStreamWriter since the one provided by Sun is
not part of the public API
Merged AbstractDataComponent and DataComponent interfaces for better API
clarity + included JSON data stream reader/writer
Added new ValidationException used in validateData methods
Added helper constructor to BinaryComponent
Removed SWE Reference object since it is not used anymore (it was
replaced by a String in codeSpace property) and conflicts with GML
Reference
Added Unit object as value of UnitReference property
Added GML bindings for use by O&M and SensorML + various improvements
for SensorML