no more 100% height, but the footer is more consistent
clean ``100%``height version without space on top or bottom

- if the page is too short, background color is not applied yet
fix background color issue
Merge branch 'feature/amb_ryan_fait_sticky_footer'

* feature/amb_ryan_fait_sticky_footer:
  fix background color issue
  clean ``100%``height version without space on top or bottom