Update the XSL file for conversion of XML to html

[larsbarring]

This is one in a string of issues that aims to improve the format of the XML version of the standard name table files, see #457 for background and overview.

With the implementation of #511 Appendix B: New element in XML file header to record the "first published date" the XLS file governing how the XML standard name table is converted into the HTML version. The specific reason is that the publication data is now recorded in a different tag, <first_published_date>, than before. The previously used tag, <last_updated> is now used to record exactly what is says.

At the same time, it would be useful to make the minor changes to also display the content of the new <conventions> tag in the HTML version.

[larsbarring]

This is the final issue in a string of issues that aims to improve the format of the XML version of the standard name table files, see #457 for background and overview.

I have now tested the full chain of changes and how the new XML format may look when transformed to HTML. There are some small changes to the XSL stylesheet file that governs the translation from XML to HTML. Before making a PR I just want to share the only small layout change that was not necessary, but maybe useful. The only change is related to the header information, here is a screen clip:

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This is just an example, please feel free to comment.

The other material change in the format was how duplicate aliases are represented in the XML file. It works out nicely without any changes. This is the result if I search for surface_carbon_dioxide_mole_flux:

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[JonathanGregory]

These changes look good to me. I agree the new information is useful in the header. Thanks for opening this issue, and for the large amount of careful work you've done on the whole series of them, @larsbarring.