Prometheus - Donation and payment store

Changelog

1. Fix error when visiting Prometheus installations that are installed in sub-directories.
2. Fix styling for featured packages

Modified files

Web

1. app/scss/themes/prometheus/_variables.scss
2. app/scss/themes/prometheus/components/boxes/_store_box.scss
3. compiled/css/site.css
4. compiled/essential.js
5. compiled/js/site.js
6. inc/footer.php
7. inc/functions.php
8. inc/header.php