[Kst] special trick for datasource in *.kst

[Ted Kisner]

I'm trying to get the healpix datasource to support saving / reading from a 
kst file.  I've added a QDomElement to the constructor (in the same way as 
the ascii datasource) and added functionality to parse a QDomElement as well 
as overloading the KstDataSource::save function.  The kst file gets created 
properly, but I'm having trouble loading.

Before I work on debugging the datasource- is there any place in the code 
where I need to tell it that the healpix datasource supports this 
functionality?  I searched around for any special "exceptions" made for the 
ascii datasource, but couldn't find any...  I'm sure it's probably a bug on 
my end, but just wanted to ask if there is a quick fix somewhere that I don't 
know about.

-Ted