Fix typos found in reviews
This MR addresses the following issues:
#106 (closed), #107 (closed), #109 (closed), #115 (closed), #120 (closed), #125 (closed), #128 (closed), all of which focus on typos, broken links, and slightly confusing information. The only piece of these that I'm not 100% sure how to fix is the broken DOI link for Jones and others 2022: Page Not Found (usgs.gov). This DOI link also appears here: Techniques and Methods 11-A3 - Federal Standards and Procedures for the National Watershed Boundary Dataset (WBD) (usgs.gov), so this seems a bit larger than hyswap getting the wrong link, but I changed the link to go to the "Techniques and Methods" page, rather than the DOI.