Update docstrings section for clarity and fix code sample indentation

[cdcme]

ReStructured Text is typically abbreviated as RST, not reST, so I've changed that here since reST is too much like REST. I've also added a parenthetical spelling out what RST stands for for clarity and fixed the indentation in the code sample.

[dirn]

reST and RST are both acceptable abbreviations. I've personally always preferred the former as it better reflects the style of reStructuredText.