This allows doing targetted rebuilds to cut down on the build time significantly,
if you know that you don't need to regenerate every page.
Usage: make html SPHINXOPTS=-j12 FILELIST=index.rst
This commit rewords some messages in the makefile to make them simpler
and more natural sounding. It also corrects a minor grammatical mistake
where the word “a” was used before a vowel sound.
It's the only tutorial where we used the extension for *3* formulas which anyway
ended up as fairly low res static images generated by sphinx.ext.imgmath, so
requiring ~1 GB of LaTeX setup for it is overkill.
The replacement pictures are the ones generated by sphinx.ext.imgmath, we could
replace them by higher resolution ones.
Improve CI build times by using a dummy builder for (empty) output, dropping LaTeX, and disabling some Sphinx extensions when building for CI (GDScript lexing, creating a search index, and generating HTML description tags).
In my tests, this improves Travis CI build times: from up to 30 minutes down to 2 minutes.