RFC: New layout for 2.53

[Akim Demaille]

Hi people,

You might have noticed, I enjoy moving the files all around :)

There are two issues I would like to address in 2.53 that involve
changes in the layout.

1. More macro sets
2. More languages

I expect to move to autom4te in 2.53, and at home I have started
working on it.   autom4te will also be the driver for Autotest, M4sh,
and M4sugar.  Some other might arrive.

But then we should install these different sets in different
directories IMHO.  Eg

../Autoconf/M4sugar
../Autoconf/M4sh
../Autoconf/Autotest
../Autoconf/Autoconf

I personally would like to stop using acgeneral.m4, but
Autoconf/general.m4 and so on.  What do you think about that?  I
propose that the srcdir be alike installdir, i.e.,
autoconf-2.53/lib/Autoconf/Autoconf/general.m4 etc.  There is already
an autoconf-2.53/lib/Autoconf/Struct.pm in my autom4te proposal, that
matches what we did for Automake.

I would also like to move the Autoscan files (acheaders etc.) into
../lib/Autoconf/Autoscan/headers.


To address 2, I tend to think we should have some separation according
to the base language.  It seems obvious at this stage that we need at
least C (and C89 and C++), and Fortran (77, 90, 95, and maybe
preprocessed declinations).

But what file names?  Since I proposed to also change the names of the
m4 files, I would simply suggest ../Autoconf/Autoconf/fortran.m4,
../Autoconf/Autoconf/c.m4.

How does it sound?