Implemented multiple tree support for dragdrop to transfer data between multiple trees.

git-svn-id: https://primefaces.googlecode.com/svn/primefaces/trunk@9213 5a70e874-a5cb-11dd-8af2-493fb0bb9f7c
#5635

git-svn-id: https://primefaces.googlecode.com/svn/primefaces/trunk@9219 5a70e874-a5cb-11dd-8af2-493fb0bb9f7c