* Create RTL stylesheets using `gulp-rtl`
* Handle RTL stylesheet special cases
Certain blocks of Sass were set to bypass "rtlcss" using ignore
comments. Certain icons had to be flipped 180 degrees.
* Switch stylesheets when locale changes
A second stylesheet has been added to each HTML page for use with
right-to-left locales. It is disabled by default. It is enabled on
startup if a RTL locale is set, and when switching to a RTL locale.
Similarly the LTR stylesheet is disabled when a RTL locale is used.
Unfortunately there is an unpleasant flash of unstyled content when
switching between a LTR and a RTL locale. There is also a slightly
longer page load time when using a RTL locale (<1s difference). We
couldn't think of an easy way to avoid these problems.
* Set `dir="auto"` as default on `TextFields`
