ticket:10992: BRS line 52, update C readme for RC

git-svn-id: http://source.icu-project.org/repos/icu/icu/trunk@36534 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10992: fix memory leak


git-svn-id: http://source.icu-project.org/repos/icu/icu/trunk@36539 251d0590-4201-4cf1-90de-194747b24ca1
ticket:10992: urename.h update

git-svn-id: http://source.icu-project.org/repos/icu/icu/trunk@36544 251d0590-4201-4cf1-90de-194747b24ca1