Add separate m4 dir to avoid intltool/libtool splattering over gnulib
Add separate m4 dir to avoid intltool/libtool splattering over gnulib

If no generic -I m4 directory is listed, libtool & intltool will
splatter their files all over those belonging to gnulib. This gives
wierd, unpredictable build errors depending on whose file was copied
over most recently.

* Makefile.am: Add -I m4 flag

jwendell/gtk-vnc,jwendell/gtk-vnc,jwendell/gtk-vnc,jwendell/gtk-vnc,jwendell/gtk-vnc