ticket:9101: export helper classes from normalizer2impl.h

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/markus@33139 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9101: export singleton classes from mutex.h

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/markus@33140 251d0590-4201-4cf1-90de-194747b24ca1