Massive upgrade of the build tools under Linux/Mac OS X & Unix

[Sylvestre Ledru]

Hello,

I just pushed a massive upgrade of the autotools used in the Scilab
build system.

* The most important point is the update of libtool (1.5.26 to 2.2.6a)
asked by Jonathan. As said in the bug #4279, it greatly increases the
compilation speed.
Thanks for pointing that out. I should have done this sooner.

For example, on my computer, I get
$ time (./configure && make) 
[...]
real	12m10.433s
user	9m25.235s
sys	1m44.595s

* automake has been updated to version 1.11

* autoconf has been updated to version 2.64

* I also removed from Scilab source tree a embedded macro from autoconf
(m4/libs_by_debian.m4). It was a modified file from autoconf by Debian
which was fixing some autoconf bugs. Fixes which has been applied
upstream since then and it was starting to cause some issues.

I am aware that these versions may not yet available under Ubuntu
(jaunty has the right version of libtool) and some other distributions.
I am sorry for the problem it can causes but I had to push them now in
order to have some time to fix the new bugs produced by
libtool-bug-factory.

As a workaround, you can:
* remove the option --enable-maintainer-mode
* ask me to rebuild {configure,Makefile.in} when needed
* retrieve the packages from http://packages.ubuntu.com/jaunty/libtool
(etc)

Please, don't hesitate to report any bugs or undesired changes to:
http://bugzilla.scilab.org/

Sylvestre