Updated changelog, documentation, and bumped version number to 0.19.0
Limit nose verbosity caused by using log_to_stderr. In the future we should use a QueueHandler/QueueListener setup for logging.
Clean up a few minor things in experiments.py
Fix tuple unpacking issue added by previous change.
Use bundled version of miniconda.sh instead of downloading it from server, since the web server seems to go down every once in a whiel.
Remove unnecessary apt-get update from .travis.yml
Merge branch 'release/0.19.0' into develop