Makefile: Do not install built-ins as MSYS does not support file system links

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Makefile: Use MakeMaker to build the Perl libraries

This way the libraries get properly install into the "site_perl" directory
and we just have to move them out of the "mingw" directory.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
MinGW: Do not redefine _stati64

With MinGW runtime 4.0 this interferes with the previous definition from
stat.h. As the macro is unused, simply remove it.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
MinGW: Fix stat definitions to work with MinGW runtime 4.0

Also, mingw_lstat() was never used instead of stat() on Windows, so adjust
the comment accordingly.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
git-compat-util: Avoid strcasecmp() being inlined

This is necessary so that read_mailmap() can obtain a pointer to the
function.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Windows: Do not redefine _WIN32_WINNT

With MinGW runtime 4.0 this interferes with the previous definition from
sdkddkver.h.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>