Sphinx docs don't build on Mac

[vygr]

cd into doc folder.
make clean
make html

Error reported here is:
Running Sphinx v1.8.3

Extension error:
source_parser for 'restructuredtext' is already registered
make: *** [html] Error 2

That's after using Macports update to get all the latest updates and pulling all the Sphinx packages with:

pip install -r Requirements.txt

[vygr]

@traverseda Alex is this something you might be able to help with ? Thanks.

[vygr]

After a complete purge of all pip related Sphinx packages and a reinstall I now get:

Running Sphinx v1.8.3
making output directory...
building [mo]: targets for 0 po files that are out of date
building [html]: targets for 10 source files that are out of date
updating environment: 10 added, 0 changed, 0 removed
reading sources... [100%] index
../README.md:: WARNING: image file not readable: ./screen_shot_1.png
../README.md:: WARNING: image file not readable: ./screen_shot_2.png
../README.md:: WARNING: image file not readable: ./screen_shot_3.png
looking for now-outdated files... none found
pickling environment... done
checking consistency... /Users/Chris/Documents/Asm/ChrysaLisp/doc/TUTORIAL.md: WARNING: document isn't included in any toctree
done
preparing documents... WARNING: unsupported theme option 'vcs_pageview_mode' given
done
writing output... [100%] index
generating indices... genindex
writing additional pages... search
copying static files... WARNING: html_static_path entry u'/Users/Chris/Documents/Asm/ChrysaLisp/doc/_static' does not exist
done
copying extra files... done
dumping search index in English (code: en) ... done
dumping object inventory... done
build succeeded, 6 warnings.

The HTML pages are in _build/html.