ENH: make f2py an executable module

[juliantaylor]

allows pep 338 execution via python -mnumpy.f2py

[juliantaylor]

one could remove some duplication by using that file in f2py/setup.py where the shebang is added, thoguh I don't know whats the best way to get the f2py module path. is setup.py ever executed out of source?

[juliantaylor]

updated with less duplication after based on suggestion of @mgaitan, but I don't know if that works on windows
@jaimefrio can you test if the f2py binary still works?

[jaimefrio]

It will have to wait until Tuesday: I have retired my old Windows laptop, and now have a shiny Mac, but still have access to plenty of Windows boxes at work. What exactly do you want me to test?

[rgommers]

The main numpy setup.py is exec'd by setupegg.py, but I don't think you have to worry about f2py/setup.py usage other than via distutils/setuptools.

[rgommers]

I guess test that python -mnumpy.f2py <any_fortran_file> works + that scipy builds?

[juliantaylor]

no, I need tested that the f2py "binaries" still execute, they changed from text files with #!/usr/bin/python to #!/bin/sh

[juliantaylor]

mh just booted my windows vm, does not work :(

[juliantaylor]

updated to a different method

[rgommers]

If you tested this and it does work on Windows (+ TravisCI is happy), then I'd say go ahead and merge it.