generate regions module/css/imgs for frontend projects (bug 1099282)

Will create a regions.js module that returns something like:

    {'de': gettext('Germany'), 'fr': gettext('France')}

Will create a regions.styl module that looks like:

    $regions = de fr;
    for $region in $regions
        .region-{region} {
            background-image: url('../img/icons/regions/{region}.png');
        }

Then sets the dist/img/regions directory to only contain region flag images for supported regions.
Like use a Python templating library?