Use a tag for the global tag list item

Instead of forcing the global tag list to be a list of some kind, use a
tag to identify the tag list item.

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>
Initial Bootstrap3 support

Use col-xs- AND span- classes for the archive & recent entries, to
support both bootstrap2 and bootstrap3.

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>