Added some structural markup

Signed-off-by: brandondove <brandon@pixeljar.net>
added a newline at the end

Signed-off-by: brandondove <brandon@pixeljar.net>
Merge branch 'master' of github.com:brandondove/usgovapi
Added main navigation that links to petitions list

Signed-off-by: brandondove <brandon@pixeljar.net>