Merge pull request #1421 from lilleswing/write-errors

- pip install coveralls

- python setup.py install

script:

- nosetests --with-flaky -a '!slow' --with-timer --with-coverage --cover-package=deepchem

- nosetests -q --with-flaky -a '!slow' --with-coverage --cover-package=deepchem

  -v deepchem --nologcapture

- if [ $TRAVIS_PYTHON_VERSION == '3.5' ]; then

      find ./deepchem | grep .py$ |xargs python -m doctest -v;