Cluster matrices - add to the basedata object and plot them using the GUI

[GoogleCodeExporter]

Run a cluster analysis.  You cannot see the matrices used in the clustering 
unless you export them via the cluster export methods and then re-import.  This 
is clunky as one cannot visualise the matrix unless one transposes the BaseData 
and uses the View Labels tab.  Even then, it is not easy to see the spatial 
arrangement of the matrix values as the View Labels tab is not set up to do so. 


When plotting the matrix, the user should be able to click on a cell and see 
the remainder of the cells coloured by the matrix values for the respective 
pairs (selected cell vs each other cell).  This allows an interactive 
exploration of spatial patterns of turnover and is potentially extremely 
powerful when used in conjunction with analyses such as GDM and species 
turnover correlograms.

Original issue reported on code.google.com by shawnlaffan on 9 Jan 2011 at 10:46