updated installation page of documentation, and changed "Download" button on index.html to scroll to bottom where multiple installation options are featured
getting the scrolldown to work required removing the fixed positioning on #action and on the footer
The "@import url()" statement for loading Lato from Google Fonts
was ignored because "@import are not allowed after any valid statement
other than @charset and @import" according to the W3C CSS Validator.
Also remove the line for importing line-icons.css which no longer
exists.
