Updates docstring on apply

        This methods returns the number of jobs submitted. The job status is then asynchronously

        updated as the jobs complete.

        Functions passed to this method can be a string in the form `module.function_name`. When passed this way,

        the function will be discovered in the `autocnet` root. For example, `spatial.overlay.place_points_in_overlaps`

        can be passed to apply the `place_points_in_overlaps` function defined within autocnet. Alternatively, a function

        can be passed that will be pickled and sent to each child job. The pickled function must inline all needed

        dependencies (e.g., import math).

        Functions passed to apply can be applied to objects or arbitrary iterables. In the case of object, the 

        `on` parameter defines how to specifiy a specific autocnet data structure. For an arbitrary iterable, any

        python iterable can be passed. The first argument passed to the function is the element from the iterable. For

        example, if `on = [[1,2,3], [4,5,6]]`, the first argument passed to each function invocation will be

        `[1,2,3]` and `[4,5,6]`, each in an independent job.

        Parameters

        ----------

                   function requires imports external to this library, those imports must be made

                   within the function scope.

        on : str

        on : str / list

             {'edge', 'edges', 'e', 0} for an edge

             {'node', 'nodes', 'n' 1} for a node

             {'measures', 'measure', 'm', '2'} for measures

             {'points', 'point', 'p', '3'} for points

             an arbitrary iterable upon which the function is applied.

        args : tuple

               Of additional arguments to pass to the apply function

                     is being used to orchestrate queue population and another process is being

                     used to process the messages. Default: False.

        exclude : string

                  nodes to exclude from the processing jobs, passed to slurm

        Returns

        -------

        job_str : str