Executor

---------------------------

- Extend ``ExternalCommandFailed`` to expose ``command`` and ``returncode`` attributes.
- Get test coverage up to 100%.
- Fixed Sphinx documentation warning about missing static directory.
- Added a simple ``Makefile`` for common project maintenance tasks.

.. _Release 1.4: https://github.com/xolox/python-executor/compare/1.3...1.4

---------------------------

- Added support for ``fakeroot``.
- Added a ``which()`` function.
- Submit test coverage from Travis CI to Coveralls.

.. _Release 1.3: https://github.com/xolox/python-executor/compare/1.2...1.3

---------------------------

- Improved Python 3 compatibility:
- Remove irregular raise syntax.
- First experience with bytes vs strings.
- Documented supported Python versions (2.6, 2.7 and 3.4).
- Started using Travis CI to automatically run the test suite.

.. _Release 1.2: https://github.com/xolox/python-executor/compare/1.1...1.2

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Improved the documentation.

.. _Release 1.1: https://github.com/xolox/python-executor/compare/1.0...1.1