[XML-SIG] SAX 2.0: Properties and features

[Lars Marius Garshol]

Extra properties/features:
--------------------------

 - feature: is-incremental, used to tell whether the parser supports
            the IncrementalParser interface or not.

 - property: parser-name, the name of the parser

 - property: parser-version, the version of the parser

 - property: driver-version, the version of the driver

--Lars M.