Brython

The main change in this release is performance improvement : thanks to various optimisations, the [pystone test](https://github.com/brython-dev/brython/blob/master/www/speed/benchmarks/pystone.py) runs 2.5 times faster than with the previous version. It is now 15 times slower than CPython, which is still much, but it was hundreds of times slower a few months ago.

Another change is the implementation of list comprehensions and generator expressions, now using self-executing anonymous functions.

The complete changelog is included in the release files.

This is mostly a bugfix release, with a new implementation of QUnit tests by Olemis Lang.

This is mostly a bugfix version, with a new drawing demo usable on tablets and smartphones.

Besides the usual bug fixes and improvements in compliance with Python, this version focuses on Web client development, with more attributes and methods for DOM elements, more explicit error messages, and a new demo (a 15-puzzle game) running both on PC with mouse events and on smartphones / tablets with touch events.

The main change in this release is an improved version of the page to run the
CPython suite (tests/unittests/index.html), initially written by Billy Earney.
For each method of the tested classes, a report is printed with the test result
(ok or failed), the test duration, and if the test failed, the error line and
the error message.

This page will provide a systematic way to detect bugs in the implementation
and trace the progress in the compliance with Python.

Another important change is a more robust implementation of execution frames :
not something much visible by developers, but mandatory to make the
implementation more compliant with Python.

The main changes in this release are :
- a built-in step by step debugger, developed by Amr Draz (the documentation
is in section "Testing and debugging")
- many bug fixes in built-in types str, set, frozenset, list, detected by
using the built-in CPython test suite located in Lib/test

See the complete changelog for details.