ticket:11056: Create branch for CLDR26 integration work

git-svn-id: http://source.icu-project.org/repos/icu/icu@36155 251d0590-4201-4cf1-90de-194747b24ca1
ticket:11056: First cut at CLDR 26 data - lots of errors to fix

git-svn-id: http://source.icu-project.org/repos/icu/icu@36156 251d0590-4201-4cf1-90de-194747b24ca1
ticket:11058: support nested collation rule imports; make the importer stateless

git-svn-id: http://source.icu-project.org/repos/icu/icu@36157 251d0590-4201-4cf1-90de-194747b24ca1