string and ui freeze request for cheese: countdown

["Daniel G. Siegel" <dgsiegel gmail com>]

hi there!

we have a nice patch laying aroung which enables/disables
the countdown in the menu of cheese. it provides a checkbox, 
which shows the recent state of the countdown and allows to en- 
or disable the countdown when taking a picture.

therefore it consists of one new string "countdown" and the new menu entry.

advantages for the users: they can en/disable the countdown easily from within the program.

patch attached here:

http://bugzilla.gnome.org/show_bug.cgi?id=511160

best regards,

daniel