The evenly distributed space causes a lot of whitespace and otoh. cut
items, so we use the items internal size as indicator IF the item is a
textbutton (the regular usecase in fluxbox)
Also publish the function to be triggered from outside (because the
caller can, in theory, much better compress several text changes)
WindowMenuAccessor returned strange alpha values if compiled
with 'g++ -Os'; unholy black magic happens if template<int> faces
functions returning only 'usigned char'.
