As numpy is Python 3 only, these import statements are now unnecessary
and don't alter runtime behavior.

After the recent patch to CCompiler.spawn, the file-paths no longer need manual quoting - that's handled as needed within subprocess.

This also states our assumption that our paths do not contain commas.
If we care about this, we could adopt the approach used by https://github.com/rust-lang/rust/issues/38795.

Tested for gcc locally by looking at the error messages of `subprocess.check_call(["gcc", r'-Wl,spaces and no quotes'])`

Other fortran compiler changes not tested, but assumed to be broken in the same way.

Fixes #12882

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

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.

 * Remove FCompiler.get_version_cmd, FCompiler.get_flags_version,
   FCompiler.get_linker_so_cmd, and FCompiler.get_linker_exe_cmd;
   subclasses should do this in FCompiler.update_executables()
 * FCompiler attributes .compiler_f77, .version_cmd, etc., are now
   properties that read from the .executables dictionary.
 * Update intel.py and absoft.py for above
 * Add extra asserts for defensive programming. Most of our problems
   here seem to come from bad values being generated, and the error not
   being caught until later.
     * must call FCompiler.customize() before FCompiler.get_version();
       command/build_ext.py and command/config.py updated
     * verify that commands make sense earlier -- must be None or
       lists of strings

Also,
 * add IA-32 as another pattern to search for in 32-bit Intel
   compiler version.
 * minor formatting
 * add debugging helpers to environment.py:EnvironmentConfig class