Add new Getting Started page

Modified content in start-en.hbs to match the new theme, 
Added page specific css in content/_base,scss
Modified colours in main/_base.scss and footer/_base.scss
Modified link colours in _variables.scss 
This CSS will never be applied since there is no newdesign class in the page. Also it seems the changes were being made to the main pages any way so no need for newdesign anymore.