ticket:10640: Add == operator support.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@35063 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10640: Fix compile error.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@35064 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10640: Make subclasses TimeUnitFormat and CurrencyFormat work with new MeasureFormat.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@35065 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10640: Make replace 'h' with 'H' more efficient.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@35067 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10640: Properly document and enclose internal API in #ifndef U_HIDE_INTERNAL_API.

git-svn-id: http://source.icu-project.org/repos/icu/icu/branches/tkeep@35068 251d0590-4201-4cf1-90de-194747b24ca1