Language files updated

Added Guest Mode error message
Countdown for jQuery v1.6.3.

Sources of JavaScript countdown library by Keith Wood
Guest Mode Countdown

Set an interval where Guests can add a track to the playlist every 30
seconds.
Include jquery countdown library for guests only
JS cleanup
added getGuestCountdown() to the API
Guest countdown configuration UI

Define the guest track-add interval in Amarok configuration UI
Version 1.5

Updated assets filenames, for http caching
Updated README