Speed up documentation generation

[tamuri]

Improving the time taken to generate the docs would facilitate quicker deployment
Ideas:

• Remove linkcheck as part of doc build because most links are behind paywall and so fail the check (and, we're not actively checking these)
• Instead of generating tables from the resource files, integrate and use an online viewer (example) - this would work for all files that are in CSV format.
• Sphinx seems to be regenerating html files for unchanged source files. Not sure why.

[tamuri]

Not sure why.

• Remove -f argument for sphinx-apidoc

• Remove {postargs:-E} for sphinx-build

• Remove sphinx.ext.viewcode