Moved run_with_vertical_hseq to hyperion.model.helpers
Updated changes.rst
Raise an exception when modifying a dust file in memory that is then used in a model that is written with the copy=False option
Added note about options for Model.write and AnalyticalYSOModel.write, and mentioned the ``merge_if_possible`` option.
Try and prevent sphinx issue
Read back in monochromatic settings when using ``Model.read``
Fixed import for coverage testing
Updated copyright
Updated download URL
Added .travis.yml
Made dependency installer script Python 3-compatible, and added verbose option
Enable --verbose option for Travis, and fixed failing test
Fixed failing test
Merge pull request #44 from astrofrog/travis

Added .travis.yml
Test for negative, nan, and inf values in spectrum
Removed debugging print statements
Only require fnu to be positive, not strictly positive
Fix logic for checking fnu is positive (should only be positive not strictly positive)
Added instructions for monochromatic radiative transfer, and tutorial example demonstrating pure scattering
Fixed URL in README.md