style: new button state btfEnabled
style: new style methods for checkbox customisation
checkbox now uses new fpgStyle methods for the painting of the checkbox image
uidesigner: Align Left button was 2px larger than other align buttons.
combobox/editcombo: Internal button painting now only done in HandlePaint

Painting outside the HandlePaint() is often a source of problems.
style: new fpgStyle methods for painting a ComboBox widget
ComboBox/EditCombo now uses the new fpgStyles API.