This modifies and hopefully improves the layout of all cgit pages:
* Remove the header from all pages and replace it with a sidebar;
most pages have sufficient width but many needs more height.
* Add a dropdown-box to switch between branches, using a one-liner
javascript to reload the current page in context of the selected branch.
* Include refs found below refs/archives in the sidebar, appearing as a
set of menuitems below a 'download' heading.
* Include the brand new cgit logo
Signed-off-by: Lars Hjemli <hjemli@gmail.com>
