Documentation cross-reference and table improvements

[cefect]

We're using some pretty difficult syntax and features... not your fault... and largely owing to having to port from MS word a few years ago.

I added a ./docs/CONTRIBUTING.md with some ideas how we can improve the document and workflow. Specifically to the number of tables (and figures) this means using the 'numref' role to automatically number things (so we don't have to renumber the whole section anytime something changes. Similarly, I noticed many of the cross-references have weird spacing (e.g., FIgure1-2 instead of Figure 1-2). Finally, many of the tables are unreadable owing to excessive column widths (e.g., the Table "CanFlood model level summaries").

The following should be addressed per the new CONTRIBUTING.md guidelines:

• revise all figure and table references to use the 'numref' roll (rather than manually number). Not all figures need a number. We may lose the section number, but this is fine.
• revise all cross-references to be human readable e.g. Table1.1 should be revised to Table 1.1 (numref will automatically do this for tables and figures, but sections may need to be cleaned manually).
• check the width of the tables. Any that are unreadably long should be converted to a csv-table to get the text to wrap.

[cefect]

For re-building tables, it may be easier to use the original manual .docx which is here.