Removes the visually hidden class on menus.

They shouldnt be hidden by default.
Removes irrelevant comment.
Changes the main file structure from separate master stylesheets to a single main.scss file and a legacy.scss file for browsers that dont suppport media queries.
Moves out all helper file imports to a _helpers partial, so that both main.scss and legacy.scss so they both have access to it without requiring a duplication of screen.scss occuring in IE
Main now imports _helpers directly, rather that proxying through _screen
Removes a file extension from sass imports
Updates directory structure for discussion
Merge branch 'feature/master-import-files'

* feature/master-import-files:
  Updates directory structure for discussion
  Removes a file extension from sass imports
  Main now imports _helpers directly, rather that proxying through _screen
  Moves out all helper file imports to a _helpers partial, so that both main.scss and legacy.scss so they both have access to it without requiring a duplication of screen.scss occuring in IE
  Changes the main file structure from separate master stylesheets to a single main.scss file and a legacy.scss file for browsers that dont suppport media queries.