Multi-line docstrings

[MGNute]

Most or maybe all of the functions have only single-line docstrings currently and lack a longer description of what the function does and how it operates (per PEP 257), and I personally find those to be very helpful for development. Unless there's a specific reason why those have been excluded, I'd like to create a branch specifically for proper multi-line docstrings with the second, more elaborate section. Open to discussion about guidelines for that though.