Draft: Add local documentation

This is documentation simply copy/pasted from the official Google doc. Having documentation included with the pipeline may be of use when internet access is unavailable. Furthermore, for the sake of tracking changes in the documentation, it is nice to have it included in the git repository. Sphinx is the standard documentation system for Python (for example, see astropy, numpy, matplotlib, etc). The makefile can be used to make html, latex files, etc.

To build local documentation, make sure you have sphinx installed:

conda install sphinx
conda install sphinx_rtd_theme

Next, cd into the doc directory and run make html. Open doc/build/html/index.html to read the documentation.

Warning: make sure to add the resulting doc/build directory to your .gitignore file so that you don't accidentally commit the generated files to the repository.

Note that it is possible to auto-regenerate this webpage with each commit to master, and allow it to be hosted as a website on GitLab or ReadTheDocs.