Fossil

This is the first check-in on the windowscompilers branch and it adds the Digital Mars C compiler

The user should have dmc installed in c:\DM with zlib in c:\DM\extra\lib and c:\DM\extra\include.

typing c:\DM\bin\make -f win\Makefile.dmc builds fossil.exe in dmcobj

The following files were edited or added:

Checks if one of the windows compilers is used. If so we define _WIN32. Defining _WIN32 is normally done by
#include <windows.h>
However most of the time we don't use windows.h.

Adding an other windows compiler is done by adding
"|| defined(__COMPILER_IDENTIFIER__)"
and maybe some special things in the files below. Like

These have all __MINGW32__ replaced by _WIN32. And in some places special processing for either MINGW32 or DMC

In popen2 the _open_osfHandle call first parameter is cast to a long. DMC refused to compile without the cast.

DMC complained that it didn't knew of time_t in rss.h. time.h came after rss.h. Switching the two solved it!

added tcl code to generate Makefile.dmc. tclsh src/makemake.tcl dmc prints to stdout the makefile. As a convienience to the end-user I added the win/Makefile.dm...