[Kde-bindings] Add option to build Qt 3 support members into qt smoke libs

[Chris Burel]

Hey guys,
So the whole reason I started writing PerlQt4 is because the company I
work for was still using PerlQt3.  Now that PerlQt4 is nearing
completion, we're looking at porting our apps to use it.  The easiest
way to do this to begin with is to use the Qt 3 support layer.  I've
added a qt3support smoke module, which contains all the classes
defined in the Qt 3 support layer (aka, all the "Q3*" classes), but
that doesn't catch the methods in QtCore or QtGui that are for Qt 3
compatibility.  To get that to happen, we'd just need to add an
"add_definitions( QT3_SUPPORT )" to the necessary cmake files for each
smoke lib, and add some option in cmake for the user to turn it on.
(or just throw it on the end of qtdefines, which is what I did to
test).

I know some people dislike the Qt 3 support stuff to begin with, so I
thought I'd ask before changing anything.

-Chris