a few changes

- Deletion of facebook, nothing can be done in javascript considering
that we want to send an alert in the future, and to do it in php we
would need to make it a php file to add php inbetween the html, which is
a problem because it won't run on local storage, which is the goal of
the coursework
- Changed the HTML template to make it better looking on smaller screens
- CSS changes:
- top currencies: data centered and adapts to the screen size
- deletion of useless rules
- beer price: bigger flags and bolder price
- JS changes:
- minor fixes
- separated HTML & JS
- email and threshold value check
- cleaned the code
- PHP changes:
- whatever
- like anybody cares