structural refactorings, Contravariant type class, Predicates, fixed UTF-8 maven warning

git-svn-id: http://highj.googlecode.com/svn@164 bdcd8b68-9dcc-aa74-f1b9-b4da3e61a8cc
improved Stream

git-svn-id: http://highj.googlecode.com/svn@165 bdcd8b68-9dcc-aa74-f1b9-b4da3e61a8cc