ticket:10273 Plural Rule Cleanup, work in progress.

git-svn-id: http://source.icu-project.org/repos/icu/icu@34006 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9101: canonical tail closure, see ticket:5913 and ticket:9319

git-svn-id: http://source.icu-project.org/repos/icu/icu@34007 251d0590-4201-4cf1-90de-194747b24ca1