Updated to html5 and added txt files

Changed doctype tho HTML5
Fixed HTML so that it validates
Added robots.txt (no rules)
Added humans.txt
Added gruntfile.js and package.json

Added a gruntfile that allows you to lint your generated site using the
grunt-html plugin. Excluded grunt.js, package.json and related files from
being copied to the _site folder.
Fixed HTML so it validates
Fixed HTML so it validates
Updated readme and config