read build version from maven meta data

git-svn-id: http://primefaces.googlecode.com/svn/primefaces/trunk@9783 5a70e874-a5cb-11dd-8af2-493fb0bb9f7c
#5841

git-svn-id: http://primefaces.googlecode.com/svn/primefaces/trunk@9784 5a70e874-a5cb-11dd-8af2-493fb0bb9f7c