Currently the overlay text, like stats for example, are drawing with
the widget_label font style size but using widget's weight. This is
just because UI_fontstyle_set is not called. Without this call we can
get a jiggling of the overlay text if these two styles differ in
weight. This PR also makes an (unnoticeable) correction to the font id
used in fontstyle_set_ex. uiFontStyle's uifont_id is not always the
same id as regular font ids, but here they are confused.
Harley Acheson