[graphic-forms-devel] another API cleanup

[Jack Unrue]

Just in case anyone happens to read the archive before
I release version 0.3.0, I'm also making two corrections
to the existing :style initarg for top-level windows:

1) the value of the :style initarg will be a list to make it
consistent with other classes that also use that initarg

2) I'm removing the style- prefix from those keywords

--
Jack Unrue