Since DynaMAGNA++ uses pthreads, we need a POSIX compliant compiler with
pthreads support for it to work.

Note, the DynaMAGNA++ GUI uses FLTK (Fast Light Toolkit). So FLTK needs to
be installed in order to compile it. FLTK is statically linked into
DynaMAGNA++, so there's no need to install anything to run the executable
itself.

In Unix and Mac OS X, you can used gcc and its variants. You will need
to install FLTK.

To compile in Unix, Mac, or Cygwin, run make clean and then make all
and/or make gui

The first command compiles the CLI code. The second compiles the GUI
code.

For Windows, since Visual C++ doesn't support pthreads (and a bunch of
other POSIX stuff that I used), I opted to use MinGW.

Here is what I did specifically.

1. I went to http://tdm-gcc.tdragon.net/ and followed the instructions to
install MinGW-w64 (either 32-bit or 64-bit)
2. I installed FLTK (http://www.fltk.org/index.php)
3.  To compile with MinGW-w64, I ran make clean and then

make all and/or make gui
