Minor fix for installer styles.
Lighter footer style.
Restyle the login form.
Make further links collapsible.
Replace responsive nav plugin with a simpler solution.

responsive-nav.js is nice, but it imposes a performance issue and
we already have code for that behaviour. This is much simpler, but
still lacks some accessibility feature (aria-hidden). I'll add
those later after some proper accessibility testing.
Improved header layout on small screens.
spamblock: show captcha-example at bottom (echo/return)
dashboard: fix commentlink
Dashboard: Also show drafts
Add StopWatch for profiling.
Code refactorings. Delete not needed backward compatibility code for PHP<5.
use magnific popup
remove serendipity_editor.js from installer, cause the link got translated to the html-page
dashboard: don't die when no entries exist
proper content-type for serendipity_editor.js
dashboard: fix entries-box
Better titles for fullsize previews (media/templates).
Add 'upcoming' status msg to dashboard entries list.

Also added some general layout styles.
Give dashboard items content some room.
More verbose update notification message.