I improved the MUL build and install (and application build!)
in several ways:

  * Use pkg-config to detect glib-2.0 .  Sadly, the Makefile.ams
    are not really amenable to easy modification to support the
    resulting flags, so that's why I did what I did.  The whole
    glib include/libs thing should change...

  * Support external object tree builds, not just builds in the
    source tree.  Lots of $(top_srcdir) action here... and included
    in that morass are updates of bad things, like linking to
    <path>/.libs/libfoo.a -- ugh -- instead of <path>/libfoo.la --
    because that's how this build was set up, and it kind of wants
    to be that way for some symbol stuff I didn't care to dig into.
    I think it has to do with the way apps are built, and some
    symbol deps that the shared objs have, but like I say, I don't
    care right now.

  * Support applications built from the installed version of MUL.
    This means we had to install all the headers, and it means that
    we moved from using config.h to mul_config.h , to minimize
    future chances of config.h collisions, heh.  We also install
    the application source skeleton (that has the application
    main()) in $(prefix)/share/openmul/app_mul_main.c or whatever.
    Works like a charm; no more funky app build foo.