Python code readme: scipy installation instructions

[palmerst]

Installing scipy on Windows needs more detailed instructions. The scipy website provides a github link to "Official source code (all platforms) and binaries for Windows & Mac OS X", but I cannot find the binaries at this location. Building from source on Windows seems difficult, and is even recommended against at the scipy website.

There is another link to sourceforge, however this is noted as legacy releases only. There are binaries here, but is this the correct version?

[bmaclach]

I added some instructions on a different installation method for Windows users. Let me know how this works for you.