bug with wxVariant

[Sebastien Senechal]

  long v; str.ToLong(&v);
are two instructions involving a declaration, when using it, that would result 
in 3 lines, 

	long v;
	str.ToLong(&v);
	SetVar(v);

My Shorter version is (exactly same number of characters typed :)
	SetVar( wxVariant(str).GetLong() );


which yields to much more readable code, and so easier maintenance.
also allows me to put it in an inline function, rather than xxx lines of codes 
for a simple conversion !

Would be even nicer with non existing :
str.GetInt32, str.GetUint64, etc... or simply 
long wxString::GetLong()


here, i know those strings are numbers... so don't need to test for that