This is minimal patch that add basic cross-compilation possibilities for
python build (configure script).

The patch add macro AC_CANONICAL_HOST.
This macro require files config.guess, config.sub. The patch don't
include them. You may obtain them from GNU automake tarbal.

As result of macro new variable $host ("host triplet":=cpu-verdor-os) is
used to detect so called "host system".

Since this is basic patch, detection of build system in native builds
based on $ac_sys_system and/or $ac_sys_release isn't replaced. This
detection isn't appropriate for cross-compilation environment as contain
values for "build system" and has to be replaces in addition by future
patches.


Also the patch posted in http://bugs.python.org/issue3718 (about
environment variable MACHDEP) isn't required for native builds, but will
help in case of cross-compilation.

The support for *-*mingw* host is enhanced to native msys environment.
This include check for device file /dev/ptmx. The MSYS report that file
exist. As the check is skipped on mingw* host os now cugwin environment
can be used too.

Also check libintl is skipped for mingw as the native build don't use it.