Committing some changes that would make it easier to Milad to check out
my code in case he choses to.
Altered the existing DaGmlHandler to parse the 2006 GML format, which is
slightly different than the 2011 format.
Completed the refractoring of PolygonPatch to CensusPolygon and
Coordinate to CensusCoordinate catching occurrances of the strings in
comments, text files, and a few method names. This aught to remove
confusion when working with the opengis.geometry classes.

Also clarified some of the class names to distinguish between 2006
census imports and 2011 census imports since they're different in subtle
ways.