Create wxPrintAbortDialog more sensibly.

Instead of having an empty constructor and filling the dialog with
controls from outside, do the work in the constructor.

This changes the meaning of ctor's 'title' argument, but this class'
terrible API made it unusable for direct use anyway, so it doesn't seem
to be harmful.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72305 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775