PUSH
====

syntax: (push <element> <place>)

This function adds a new element to an existing list
(The <place> must include a list). The new element
will be included as the first element of the list.

example:       >(setf list '(3 2 1))
               (3 2 1)
               >(push 4 list)
               (4 3 2 1)
               >list
               (4 3 2 1)