Enable extflonums in a MSVC build by relying on a MinGW-built DLL,
"longdouble.dll". The DLL is loaded on startup. If the DLL isn't
available, then `extflonum-available?' reports #f.
Instead of setting the floating-point mode globally to extended
precision, the mode is changed only just before (and restored right
after) extflonum arithmetic operations.
The ActiveX part of MysterX is gone. The `ffi/com' re-imeplemtnation
provides only core COM support.
The "mysssink" DLL is still needed, and its source is still
in the tree, but it is downloaded in the same way as other
pre-built DLLs. The DLL no longer needs to be registered with
regsvr32.
The libjpeg, libeay, and ssleay libraries for Win64 linked to
msvcr90.dll, because of the way that they were compiled with
MSVC 2008, but msvcr90.dll is not included with Win7, and
redistributing it is problematic. The new variants of the libraries
link instead of msvcrt.dll --- which you're not supposed to do
according to MS, but that's the way libraries like Gtk are
built, and it seems to be the right approach. See also
http://kobyk.wordpress.com/2007/07/20/dynamically-linking-with-msvcrtdll-using-visual-c-2005/
I built libjpeg-8, while the other two are courtesey of
http://www.indyproject.org.
Closes PR 12246
Instead of downloading to the build directory and then copy files from
there to the target, download directly to the target. This way no
downloading is necessary when people use a fresh build directory.
