include additional forms of INSTALL and CONTRIBUTING files on release pages
work around syntax highlighter stripping leading blank lines
add metadata about page
Merge branch 'about-metadata'
re-optimize some images
move irc link after license
clean up styles for sidebars

A lot of the rules were to override the nav styles to re-normalize
things.  The nav-list isn't part of bootstrap anymore, so just repurpose
it as our own sidebar class, and remove the nav class from the sidebars
using it.  This simplifies things greatly cleans up link sizes as well
as allowing arbitrary content easier.
remove extraneous markup, unneeded after nav-list cleanup
apply sidebar alignment on page load
clean up breadcrumbs on browse, source, diff pages
update font awesome
improve styles on mirrors page
improve mirror sidebar link handling
decode url parameters when used in javascript
adjust ratings markup so it can be customized for different locations
add more sidebar icons
remove extra border on diff view
add flags to mirror page
Merge branch 'sidebar-css-refactor'
Drop older perls from travis builds