needed, and being able to define it if appropriate for further configure tests
as well as for the generated config file.

Introduced reentrant.m4 intended for our reentrant related autotools/m4 macros.

the dist tarball and remove a two duplicate file names from EXTRA_DIST
(most of it pointed out by Yang Tse)

link any executables when doing debug builds since they kind of assume
symbols provided by libcurl, but it also wrongly included acountry.c

and API changes in the progress callback (and possibly more coming up from
Steinar)

libtool cross-compiled on linux with mingw32

properly set, and the Makefile.am is now fixed to use that when building
a new package with make dist.

  check for ssize_t to make it possible to use that when receiving the send()
  error code. This is necessary to prevent compiler warnings on some systems.

- Made configure create config.h, and all source files now include setup.h that
  might include the proper config.h (or a handicrafted alternative).

- Switched to 'ares_socket_t' type for sockets in ares, since Windows don't
  use 'int' for that.

- automake-ified and libool-ified c-ares. Now it builds libcares as a shared
  lib on most platforms if wanted. (This bloated the size of the release
  archive with another 200K!)

- Makefile.am now uses Makefile.inc for the c sources, h headers and man
  pages, to make it easier for other makefiles to use the exact same set of
  files.

- Adjusted 'maketgz' to use the new automake magic when building distribution
  archives.