Fix bad behaviours of clock after the contest ends

If you open the rankings and wait for the contest to end you'll notice some strange things (that disappear if you refresh the page):

- the clock is still clickable and will show only one menu entry "Current" (this fixed by giving "display: none" to that entry too, and by giving the "open" style only if a contest is runnig or a contest has to start).
- the name of the contest is still showing, this is because of a $("#TimeView_name").text(); that should be $("#TimeView_name").text(""); instead.

Also, a bug introduced by a previous commit (clock not clickable if you're waiting for the contest to start) is now fixed by binding the click event to $("#TimeView_selector") instead of just to $("#TimeView.cont > #TimeView_selector")