Improve language switching

v1.0.3

Improve language switcher. Bump to 1.0.3

v1.0.2: Add a Plausible analytics script if configured in the customizer

• Add a control for configuring Plausible analytics
• Improve squashed thumbnails in mobile view
• Update Node Sass

Tweak CSS and incorporate fonts into sass build

v1.0.1

Update dev JS deps, incorporate fonts and tweak some CSS

Initial release

Switch from Gulp to Grunt and simplify asset pipeline.

Sources are now copied directly into js and sass rather than the
src directory. Sass directory renamed to scss

Also: bump version 1.0.0 and delete various extraneous files we're
unlikely to use.