```
* [Changed] Add basic `pico-theme.yml` to use API v3, enable Twig's autoescape
feature (no changes necessary) and register `Social` meta header
* [Changed] Use Pico's `pages` Twig function to create the main navigation
* [Changed] Improve formatting of definition lists and inline code snippets
* [Changed] Improve JSDoc class docs
```
`line-height: 1.9824;` is the result of `calc(1em * 1.4 + 2 * 0.1em + 2 * 1px / 16px / 0.85 + 2 * 0.1em / 0.85)` (`1em * 1.4` equals the line height for code (= `1.4` times), plus `0.1em` vertical padding on top and bottom, plus `1px` border width on top and bottom (`1rem` equals `16px` and considering the smaller font size (= `0.85rem`)), plus `0.1em` vertical margin on top and bottom (also considering the smaller font size).
`line-height: 1.9778;` is the result of `calc(1rem * 1.6 / 0.9 + 2 * 0.1em)` (`1rem * 1.6 / 0.9` equals the default line height (= `1.6` times) adjusted by the smaller font size (= `0.9rem`), plus `0.1em` vertical space on top and bottom)
```
* [Fixed] Fix sliding animation of collapsible menu in IE 9
* [Changed] Move Fontello font to `icon/` directory
* [Changed] Move stylesheets to `css/` directory
* [Changed] Improve Fontello font copyright notice
* [Changed] Add Droid Sans and Droid Sans Mono font files to `font/` directory,
making Pico's default theme fully self-containing
```
IE9 doesn't support sliding, but also doesn't support requestAnimationFrame(). Use setTimeout() with a delay of 16ms (1000ms / 60fps = 16.67ms) instead. This isn't optimal, but who cares about IE9... This is also true for IE8, even though we don't officially support it.
