Use default theme on readthedocs.
Add intermediate heading.
Use nature theme on RTD.
Merge branch 'master' into readthedocs
Update README.
Remove setuptools from install_requires.
Increase header levels in README.
Update sphinx config.
Add config for sphinx commands.
Merge branch 'master' into readthedocs
Fix capitalization.
Link to Python 3 library docs.
Split test.
Prepare term 2.1.