Update sphinx_rtd_theme to 3.0.1#193

pyup-bot wants to merge 1 commit intomasterj340m3/python-msquaredc:masterfrom

pyup-update-sphinx_rtd_theme-0.4.1-to-3.0.1j340m3/python-msquaredc:pyup-update-sphinx_rtd_theme-0.4.1-to-3.0.1Copy head branch name to clipboard