Autoscroll on edges for tree dragdrop, needs a bit refactor.

git-svn-id: http://primefaces.googlecode.com/svn/primefaces/trunk@9977 5a70e874-a5cb-11dd-8af2-493fb0bb9f7c
cache ignoreAutoUpdate in requestContext

git-svn-id: http://primefaces.googlecode.com/svn/primefaces/trunk@9978 5a70e874-a5cb-11dd-8af2-493fb0bb9f7c