Closes https://github.com/pyodide/pyodide/issues/604

This creates an installable `pyodide-build` Python package that we can also upload to PyPi under https://pypi.org/project/pyodide-build/ (currently uploaded the dev version to reserve the name).

There is also the identically named `pyodide-build` CLI command which replaces `bin/pyodide`.

The short term goals is to use fewer hacks with `PATH` and `PYTHONPATH`. Long term goal make it a user facing interface for building packages instead of the Makefile.
Create an installable pyodide-build package. Closes https://github.com/pyodide/pyodide/issues/604

This creates an installable `pyodide-build` Python package that we can also upload to PyPi under https://pypi.org/project/pyodide-build/ (currently uploaded the dev version to reserve the name).

There is also the identically named `pyodide-build` CLI command which replaces `bin/pyodide`.

The short term goals is to use fewer hacks with `PATH` and `PYTHONPATH`. Long term goal make it a user facing interface for building packages instead of the Makefile.
# http://stackoverflow.com/questions/16541618/perform-a-reverse-cumulative-sum-on-a-numpy-array
# pythran export reverse_cumsum(float[])
# setup: import numpy as np ; r = np.random.rand(1000000)
# run: reverse_cumsum(r)
import numpy as np


def reverse_cumsum(x):
    return np.cumsum(x[::-1])[::-1]

# http://stackoverflow.com/questions/16541618/perform-a-reverse-cumulative-sum-on-a-numpy-array
# pythran export reverse_cumsum(float[])
# setup: import numpy as np ; r = np.random.rand(1000000)
# run: reverse_cumsum(r)
import numpy as np


def reverse_cumsum(x):
    return np.cumsum(x[::-1])[::-1]
