Gtkmm 1.2.8 changes

[mark mitchell <markummitchell gmail com>]

Hello,

I had to make changes to the configure script, and source gtkmm source files, to get the gtkmm-1.2.8 code to build with m4-1.4.15 and gcc-3.4.6. Here are the changes if you are interested:

1) The configure script failed when checking for M4. It tested 'm4 --version' against  '^GNU m4 ', which I had to change to 'GNU M4' (note the caret, capitalization and spaces!)
2) proxy.h had issues
   2a) The code did not build right away.  had to replace: "obj->gtkobj" by: "this->obj->gtkobj" everywhere
   2b) change "obj->register_data(node)" to "this->register_data(node)" everywhere
3) edit base.h and replace: "return Gtk::wrap(static_cast<impl*>((*node).data));" by: 
       "return dynamic_cast<interf*>
       (Gtk::wrap_auto(static_cast<GtkObject*>
         ((*node).data)));"
4) adjustment.h has an apparently unnecessary union, which the compiler does not support, and two functions that are not properly declared:
   4a) Comment out the 3 lines "union" "{" and "}"
   4b) Append parentheses after the changed and value_changed attributes since they are functions and not variables
5) curve.h changed from
   5a) "gfloat data[] = new gfloat[i]" to "gfloat* data = "" gfloat[i]"
   5b) "get_vector(n,data)" to "get_vector(i,data)"
6) removed default arguments for Editable::get_chars in editable.cc file (they belong only in header file)

The code seems to be working fine at this point, although I have not tested it thoroughly.

Thank you,

Mark Mitchell