package version macros, pango backspace_deletes_character

["Ross McFarland" <rwmcfa1 neces com>]

in working on the the gtk2-perl bindings set we've run into several situations
where something new has been added in a version of a package which has no
version macros. one case of this problem is PangoLayoutAttr adding the struct
member backspace_deletes_character. it was apparently added with version 1.3.0
(or around there,) but there doesn't seem to be anything in the pango header
files about versions so we can't do ifdef's around access to that member. in
other modules we've had to do things with CFLAGS and pkg-config at Makefile.PL
time (essentially configure) to define version info on the gcc command lines
which is way less than ideal.

i would like (and bindings would greatly benifit from) it being standard
practice to have something like the (GLIB|GTK)_(MAJOR|MINOR|MICRO)_VERSION
scheme be required of all modules of the gtk/gnome family.

if it's just a matter of someone doing it i could probably manage submitting a
patch for at least pango, but whatever else people are interested in.

of course as always i could be missing something, if that's the case feel free
to enlighten me.

-rm