cosmetics: PEP-8 conventions.
requirements: Loosen dependency on argparse to avoid CI failures.
travis: Remove deprecated --use-mirrors from pip
travis: Allow external python packages to satisfy pip requirements.
{travis,requirements}: Allow CI failure with Python 2.6.
travis: Kill --allow-external from pip command line.
travis: Fix yaml syntax.
requirements: Bump requests version to work with Python 3.4. Closes: #241.
travis: Test the project also with Python 3.4.
travis: Disable tests with Python 3.4 for the moment.

We need to wait until there is a fix for

    https://github.com/travis-ci/travis-ci/issues/1989
travis: Try to re-add Python 2.6 testing.

We still allow tests with Python 2.6 to fail, though.
travis: Enable testing with Python 3.4.
README: Point out that there is an Android version of VLC.
README: Spell out the Python versions that we actively test for.
README: Reinclude (expanded) instructions for running the script.

Setting the PATH should not really be Windows specific.

[ci skip]
requirements: Loosen the versions of the packages.

Some of the versions that we had fixed in the `requirements.txt` file are
old (see Issue #247) and they should serve only as a baseline for what `pip`
installs.

Furthermore, we should also keep an eye on how newer versions of our
dependencies work (via the automated tests), so as to assist our users
better.
Update login request to meet new requirements
Handle file size 0 when calculating percentages

Return percentage done as 100% when file size is 0 (to prevent division
by zero exception from being thrown)
Merge pull request #253 from ERufian/master

Handle file size 0 when calculating percentages
coursera: Only run with a new enough requests library.