Run the 2to3 ws_comma fixer on *.py files. Some lines are now too long
and will need to be broken at some point. OTOH, some lines were already
too long and need to be broken at some point. Now seems as good a time
as any to do this with open PRs at a minimum.

Add `print_function` to all `from __future__ import ...` statements
and use the python3 print function syntax everywhere.

Closes #3078.

The new import `absolute_import` is added the `from __future__ import`
statement and The 2to3 `import` fixer is run to make the imports
compatible. There are several things that need to be dealt with to make
this work.

1) Files meant to be run as scripts run in a different environment than
files imported as part of a package, and so changes to those files need
to be skipped. The affected script files are:

    * all setup.py files
    * numpy/core/code_generators/generate_umath.py
    * numpy/core/code_generators/generate_numpy_api.py
    * numpy/core/code_generators/generate_ufunc_api.py

2) Some imported modules are not available as they are created during
the build process and consequently 2to3 is unable to handle them
correctly. Files that import those modules need a bit of extra work.
The affected files are:

    * core/__init__.py,
    * core/numeric.py,
    * core/_internal.py,
    * core/arrayprint.py,
    * core/fromnumeric.py,
    * numpy/__init__.py,
    * lib/npyio.py,
    * lib/function_base.py,
    * fft/fftpack.py,
    * random/__init__.py

Closes #3172

These havn't been deprecated, but I think few have heard of them, much
less used them. Before this change, running setup.py without any
arguments would result in interactive help. This patch removes that
interactive help and lets setup print its usual list of commands and
options.

All the script uses of the numpy/distutils/fcompiler compilers look
quite broken to me, but I have tried to maintain compatibility with the
earlier version of gnu.py after the removal of `raw_input`.

These removals solve an incompatibility between Python3 and Python2.
The current interactive setup help uses `raw_input`, which has been
removed in python3 and replaced by `input`.  However, python2 already
has an `input` that has different semantics.  Rather than deal with
this, I think it simpler to keep both `raw_input` and `input` out of
numpy.

Closes #3063
Closes #3079

This should be harmless, as we already are division clean. However,
placement of this import takes some care. In the future a script
can be used to append new features without worry, at least until
such time as it exceeds a single line. Having that ability will
make it easier to deal with absolute imports and printing updates.

This removes files and code supporting scons builds. After this change
numpy will only support builds using distutils or bento. The removal of
scons has been discussed on the list several times and a decision has been
made that scons support is no longer needed. This was originally discussed
for numpy 1.7 and because the distutils and bento methods are still
available we are skipping the usual deprecation period.