[Speed] perf 0.9.6 released

[Victor Stinner]

Hi,

I released perf 0.9.6 with many changes. First, "Mean +- std dev" is
now displayed, instead of "Median +- std dev", as a result of the
previous thread on this list. The median is still accessible via the
stats command. By the way, the "stats" command now displays "Median +-
MAD" instead of "Median +- std dev".

I broke the API to fix an old mistake. I used the term "sample" for a
single value, whereas a "sample" in statistics is a set of values (one
or more), and so the term is misused. I replace "sample" with "value"
and "samples" with "values" everywhere in perf.

http://perf.readthedocs.io/en/latest/changelog.html#version-0-9-6-2017-03-15

Version 0.9.6 (2017-03-15)
--------------------------

Major change:

* Display ``Mean +- std dev`` instead of ``Median +- std dev``

Enhancements:

* Add a new ``Runner.bench_command()`` method to measure the execution time of
  a command.
* Add ``mean()``, ``median_abs_dev()`` and ``stdev()`` methods to ``Benchmark``
* ``check`` command: test also minimum and maximum compared to the mean

Major API change, rename "sample" to "value":

* Rename attributes and methods:

  - ``Benchmark.bench_sample_func()`` => ``Benchmark.bench_time_func()``.
  - ``Run.samples`` => ``Run.values``
  - ``Benchmark.get_samples()`` => ``Benchmark.get_values()``
  - ``get_nsample()`` => ``get_nvalue()``
  - ``Benchmark.format_sample()`` => ``Benchmark.format_value()``
  - ``Benchmark.format_samples()`` => ``Benchmark.format_values()``

* Rename Runner command line options:

  - ``--samples`` => ``--values``
  - ``--debug-single-sample`` => ``--debug-single-value``

Changes:

* ``convert``: Remove ``--remove-outliers`` option
* ``check`` command now tests stdev/mean, instead of testing stdev/median
* setup.py: statistics dependency is now installed using ``extras_require`` to
  support setuptools 18 and newer
* Add setup.cfg to enable universal builds: same wheel package for Python 2
  and Python 3
* Add ``perf.VERSION`` constant: tuple of int
* JSON version 6: write metadata common to all benchmarks (common to all runs
  of all benchmarks) at the root; rename 'samples' to 'values' in runs.

Victor