Address bug #8601.

The fundamental problem here is that the meaning of the hourglass
field changes dynamically according to whether you're in SP or MP,
while themes are static; thus, whatever we put in as a static tooltip
in the theme is going to be wrong a lot of the time.

The fast solution is to rip this tooltip out, which is what I've done.
With some C++ klugery analogous to what's done to change the End Turn
button label in linger mode we could do something clever here, but I
don't think the small gain would be worth the extra complexity.

Anyone who disagrees with me is welcome to file a FR, or (better yet) 
have at the C++ themselves.

data/themes/macros.cfg

@@ -11,7 +11,6 @@
         id=time-icon
         #icon=misc/units.png
         icon=misc/sand-clock.png
-        text= _ "time left"
         ref=timeout-panel
         rect="=+5,=+1,+17,+17"
         xanchor=proportional