ticket:9914: Create new branch for ICU4C.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@33399 251d0590-4201-4cf1-90de-194747b24ca1
ticket:9914: Fix ICU4C DateIntervalFormat to correctly handle 2 year vs 4 year forms.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@33405 251d0590-4201-4cf1-90de-194747b24ca1