Create the new footer and include it on every page #653

Work in progress for Bounty #653.
Do you mind pulling this out into a variable or maybe a percentage of another color already defined? It just helps to have all colors defined in a single place so we can easily change them later. Check out [app/assets/stylesheets/_variables.css.scss](https://github.com/asm-helpful/helpful-web/blob/master/app/assets/stylesheets/_variables.css.scss#L10-L38)