taskMap creates a chart showing how the completed and
running tasks for a distributed job are allocated between the cluster workers over time. If the job supplied is still running then the chart will be updated every few seconds until completion (or the window is closed), allowing progress to be monitored. When the job is finished the function will exit.
This function builds on the PlotTasks function available elsewhere on the file-exchange, improving the appearance of the chart and adding more information about task allocation and relative task durations. See also Doug Hull's "PlotTasks" for clusters with large numbers of workers.