Changes - hopefully improvements - to build process on windows

I have checked in further changes to the build process.  I am attempting 
to untangle the rules for the windows installer.  I hope I haven't 
broken anything.  If I have I will try and fix it promptly.

A large part of the windows build process was controlled by 
interfaces/xmaxima/win32/Makefile and assumed the lisp was gcl.  I have 
tried to move rules closer to the files they operate on, and to remove a 
few "temporary" hacks I put in place several years ago.

After my recent changes I have successfully built maxima using gcl, sbcl 
and ccl - and all three at once.  "make install" works but I haven't 
tried to build installers using sbcl or ccl.  There are sure to be a few 
arrangements I haven't tested.

./configure --prefix=c:/maxima  \
  --enable-lang-es --enable-lang-pt --enable-lang-pt_BR \
  --enable-gcl --with-ccl=/c/programs/ccl/wx86cl.exe \
  --with-sbcl=/c/PROGRA~1/STEELB~1/10557M~1.118/sbcl.exe

I needed to use a short filename to use sbcl due to spaces in paths.  I 
am sure that is fixable with a few "" in the right spot.