[gtkada] Can_Focus

[manuel.op.de.coul at eon-benelux.com]

I found an omission in Glade. I'm using version 0.5.11.
While it produces code to set the flag Can_Default according to the "can
default"
property, this doesn't happen for the "can focus" property.
If it is set to "Yes", then <can_focus>True</can_focus> is written to
the glade file, otherwise nothing. The default behaviour seems to be
that Can_Focus is set, so code needs to be produced to unset it when
the property is "No".

Manuel Op de Coul