Updates AMS to V6.1

[ConorIA]

Replaces #348 and closes #298

Todos:

• [ ] I have not made a great effort to make the skeleton article more "RMarkdown-y". I started replacing some of the \section entries with #, but I was having compilation errors, so needed to go back to start.
• [ ] The AMS template says to use \twocolsig and \twocolcapsule when using twocol mode, but these are giving me undefined control sequence errors. I have commented out my conditional in template.tex, but would like to get the functionality working before this is merged #helpwanted!
• [x] The AMS template uses "and" before the final author name. I have used a for loop for authors (yay me), but I am not familair enough to know how to do a "if (i == length(authors)" type of statement to add the "and" before the last author entry. #helpwanted!
• [ ] I have addressed the for loops, but I had to resort to using a for loop on the last array entry. That doesn't seem to be right, but I can't figure out how to access the values of authors/last. e.g. authors/last.name throws an error and authors/last["name"] returns "true", not "Author Eight".
• [ ] News not updated yet because this may not make it into main for a while!

Thanks to @eliocamp as much of this was based on his work on the v5 template.

It looks like old releases of pandoc don't play nice with the pipes. For the record:

$ pandoc --version
pandoc 2.11.4
Compiled with pandoc-types 1.22, texmath 0.12.1, skylighting 0.10.2,
citeproc 0.3.0.5, ipynb 0.1.0.1

[cderv]

@ConorIA do you plan to keep working on this or should I take over ?

Maybe AMS has also update to a newer version than 6.1.

Enquiring about the status of this PR following my latest review

[ConorIA]

Hi @cderv, sorry to have been unresponsive to your very detailed review. I find myself very short on free time these days, and haven't been writing much after finishing my thesis last fall. I would be happy to have you take over.

The good news is that v6.1 is still the current AMS template https://www.ametsoc.org/index.cfm/ams/publications/author-information/latex-author-info/

[cderv]

Thanks for the feedback - I'll add that to my list then. Thanks for your contribution

[CLAassistant]

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