This application reads from a redis queue (RPOP) and then executes functions from a list.
The first function from the list does not receive parameter and must return true or false.
The second function from the list takes a result of reading from the redis queue (:undefined, :no_connection or string that have been read from the redis queue).
Every next function from the list gets the result of the calculation of the previous one.
While the first function return false the next functions from list not be executed