Register function with job servers with an optional timeout. The timeout
specifies how many seconds the server will wait before marking a job as
failed. If timeout is zero, there is no timeout.
*
PARAMETERS
[in] worker Structure previously initialized with
gearman_worker_create() or gearman_worker_clone().
[in] function_name Function name to register.
[in] timeout Optional timeout (in seconds) that specifies the maximum
time a job should. This is enforced on the job server. A value of 0 means
an infinite time.