Print kernel::exception occurrences during at jobs.
Print kernel::exception occurrences during at jobs.

	* src/runner/at_handler.cc: Catch kernel::exception instead of
	std::exception.

aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,aldebaran/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,aldebaran/urbi,urbiforge/urbi