Code analisys improvements (Intellij Idea) part of JAMES-1220

* redundant code removal
* for-each transforamations
* 'final' attribute added
* fixed some Thread locking issues - avoid locking on non-final objects and also on method objects
* added a lot of @Override's

git-svn-id: https://svn.apache.org/repos/asf/james/server/trunk@1451435 13f79535-47bb-0310-9956-ffa450edef68