modified ees function to summary.ees function, it takes the output from get.clusters.formatted and provides the summary

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@315 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Added class ees to get.clusters.formatted.output

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@316 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
minor modification in presenting output summary

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@317 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Created plot.ees functionality

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/eventstudies@318 edb9625f-4e0d-4859-8d74-9fd3b1da38cb