Merge pull request #15 from samoht/master

Convert and my yesterday slides to decks
Merge pull request #16 from samoht/master

Fix the dependency of commits in store.png
+cl-mirage20 slides
updates
tweaks
[make] remove deprecated `--no-opam` flag
[oasis] update `cohttp.mirage-unix` dep and regenerate
[slides] remove vi dropping
[git] tidy up `.gitignore`
whitespace
[css] fix home icon again in `site.css`
Merge pull request #17 from mor1/master

updates and bugfixes
[reveal] add minimal 2.6.2
whitespace
[reveal] break out style to prep for using 2.6.2
[reveal] more support for reveal.js-2.6.2 as well as 2.4.0
[reveal] finish adding support for reveal.js-2.6.2
[theme] start to rebuild horizon theme for reveal.js-2.6.2
[theme] update `init.js` for reveal.js-2.6.2
[theme] add renderer for reveal.js-2.6.2