* Fix JS error on index page and detect dark mode
The theindex.html page doesn't have a dark mode switch so the main
function will error because `toggleSwitch` is not defined. Checks have
been added to prevent this from happening.
Also add automatic detection of system settings for dark-mode. This
could also be done with pure css, but then the dark mode variable
declarations would have to be duplicated to work with the switch so I
went with this approach.
* Fix nimdoc tests
* Fix rst2html tests
* fix bullet/enumarated lists with many blank lines
* fix enumerated list parsing
* fix parse failure when next line after list empty
* implement arbitrary start of enumerator
* check that enumerators are in order
* remove redundant start=x if x=1 or a
* add some doc on implemented features
* update start in rst_examples.rst
* allow upper-case letters + more docs
The default HTML template for nimdoc currently initializes the dark mode switch and pragma dots when the onload event is fired. But since the onload event does not fire until all external resources (images, stylesheets, fonts, etc.) have been loaded, the light theme is shown for a brief moment before the document is fully loaded, and it switches to the dark theme. This is quite jarring, especially on slower internet connections. So let's instead initialize these things on the DOMContentLoaded event, which is fired right after the document has been parsed and the initial DOM structure is ready. This means that we now display the dark mode immediately, without having to wait for external resources to load first.
For reference, see:
- https://developer.mozilla.org/en-US/docs/Web/API/Window/load_event
- https://developer.mozilla.org/en-US/docs/Web/API/Window/DOMContentLoaded_event
I have updated the snapshot tests in `nimdoc/`, and done some manual testing of both the theme switch and the pragma dots, to confirm that this does not break anything. Please let me know if I've missed anything.
