Added an scss version

Added npm scripts to compile the scss
Added folders for the less and the scss code
Changed the path to the less version in the Gruntfile

Author: SamThilmany

Gruntfile.js

@@ -10,7 +10,7 @@ module.exports = function (grunt) {
                     ],
                 },
                 files: {
-                    'dist/device-mockups.css': 'src/device-mockups.less'
+                    'dist/device-mockups.css': 'src/less/device-mockups.less'
                 }
             }
         },
@@ -41,4 +41,4 @@ module.exports = function (grunt) {
 
     grunt.registerTask('default', ['less', 'cssmin', 'usebanner']);
 
-};
+};