Correctly install script on Windows

For #15.

So the real issue here is that the script file in Windows installs without an extension, and the shebang doesn't work on Windows. This script uses some crazy magic in distribute to basically automatically generate a batch file, which will go in the script directory, and allow installing.

I have to apologise for the diff: the new bits are lines 14-67 of the new version, and line 99 of the new version.

The alternative method, by the way, is to let setuptools build the script entirely. This would remove the binary file. The downside is that you would need to move the function that starts the script into the library itself. If you want to go that route, I can build an alternate PR that does the same thing.