Michael Bauer

Add configuration support for 'tectonic' latex engine

2

[Tectonic](https://tectonic-typesetting.github.io/en-US/) is a modern, user-friendly LaTeX engine (currently in beta state). I suggest adding support so that Tectonic can be chosen in `pandoc-set-latex-engine`

setting defaultTheme has no effect

2

Setting `params.defaultTheme` in ./config/_default/config.toml has no effect. No matter whether set to "dark" or "light", the theme is always dark. On the other hand, setting `params.themeColor` and `params.themeContrast` have the...