`toLocaleString()` is not supported in Safari, but react-intl has a polyfill, and so it is. This also localized the intro description string, which wasn't previously. This also fixes#366 by doing as @rschamp suggested and checking if the count is the default count before setting the value.
This moves all locale/translation building to a dependency, `scratch-www-intl-loader`, as well as tests associated with it. Also gets rid of the `make translations` step.
Handle localization and string loading in views only. Components should just of default text, but not the actual text for the page itself – all text handling should be at the view level.
1. Load locale strings into `window._messages` in a separate file added to `template.html`, which contains view-specific and general strings
2. Update build-locales to compile separate files
