[aggregate graph] - beta version checked in

[Peter Lin <wo...@gmail.com>]

for those who have been waiting for an easy way to graph the aggregate 
listener, I just checked in a new listener called aggregate graph. Currently 
it will generate a bar graph for a single column. the code has been checked 
into the 2.1 branch.

here is a screen capture. I plan to continue to enhance it, but for now the 
functionality is working.

http://people.apache.org/~woolfel/aggregate_graph.png

peter lin