ticket:10339: Fix build error on Cygwin/gcc (INT64_MAX) instead of (U_INT64_MAX)

git-svn-id: http://source.icu-project.org/repos/icu/icu@34122 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10273 Plural Rules, remove unimplemented getFunctionalEquivalent().

git-svn-id: http://source.icu-project.org/repos/icu/icu@34126 251d0590-4201-4cf1-90de-194747b24ca1