We use six sub-modules that aren't available in old versions. Not specifying
this requirement in the setup will lead to much less readable runtime errors.
It's particuarlly problematic for Mac OSX users because the system comes with
an old six version 1.4.1 by default.

[skip ci]

Also delete some unused files.

Also made the Travis build ensure that no warnings
are present.

These builds were previously spewing many warnings,
which was hiding warnings for important things like
accidentally using C++11-only features.

Change-Id: I56caeee9db48bc78756a3e8d7c14874630627037

Change-Id: Ieb7a2c2fbf35bc2a8fa65b915a5ecb68c83863e4

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>

Signed-off-by: Dan O'Reilly <oreilldf@gmail.com>

Checking the existence of ".git" is not the right way to check whether we
are in develop environment because we distribute source tar-balls where
such a ".git" directory does not exist. Replaced it with checking .proto
files.

Fixes #333.

- Comply with flake8, except for indentation width, which is 2.

- Move human-centric metadata to top of 'setup()' call.

- Add Trove classifiers for supported Python versions.

- Use 'find_packages()' + MANIFEST.in to avoid errors in listing
  modules and packages.

Closes #131 and #161.

Use stdlib's 'unittest' instead.

This file was broken in ada65567.

Change-Id: Ief6eccab82712be04285fc918bf0102102bbce21

Change-Id: Ie5114bde3574c6cb0c67d5852b4658287561a0d3

Change-Id: Ifb4958e4f371b36f249faa466473f851697edb5c

Change-Id: I33479e529b060e4fed532a827a386d3baecc835e

Change-Id: I34d301133eea9c6f3a822c47d1f91e136fd33145

Change-Id: Icecb25db34ae5e6d5142a2d75ca7216ba018abb2