timeline.js: StatusesSummary: use ".label" instead of ".badge" because now badge does not support colors.
timeline.js: StatusesSummary: set style class for headings so that the whole heading is clickable.
timeline.tx: it now hides status summary when the screen is small. The threshold screen width is now 768px.
busybird.css: timeline navbar now keeps its height even in small screens.
wrapper_navbar.tx: now the link to the top page becomes an icon when the screen is too small.