prepare for next development iteration
fixes IDEA-23
Jangaroo 0.9 plugin does not work with IDEA 12
http://jangaroo.myjetbrains.com/youtrack/issue/IDEA-23

Now hopefully really fixed by adding common-collections-3.2.1.jar
as 3rd-party dependency.
release net.jangaroo.idea.0.9 version 0.23
prepare for next development iteration