remove 'multi-byte' character setting from Visual Studio builds
revert last change to Visual Studio build
Rename configure.in to configure.ac.
Use uptodate dist targets.
Update configfsf.*.
Update config.* for YASM.
Treat Cygwin64 as Mingw64.
Ran "autoreconf -fi" and put back correct config.(guess|sub) files.
Fix bug in t-scan test.

Reported by Daniel R. Grayson and fixed by Leif Leonhardy.
Put back configfsf.sub trick from devel/configfsf.sub.diff.
Add option to use a user-provided Yasm with autotools build-system.
Document Yasm related options.
Remove libtool hacks.
Remove libtool hacks for C++.
Fix typos in assembly file names.
Fix for PIC code on Darwin.

Originally fixed at http://trac.sagemath.org/ticket/13137
Fix for Intel Core and Pentium4 Prescott CPUs.

Originally fixed at http://trac.sagemath.org/ticket/14172
Fix for Sun Studio compiler.
Properly quote define so that m4 does not fail.
Support *-w64-mingw* and *-*-cygwin*.