Add v1.5.12 to CHANGELOG
Add v1.5.12 to CHANGELOG
eunmin/Hystrix,eunmin/Hystrix,Netflix/Hystrix,mickdwyer/Hystrix,mattrjacobs/Hystrix,mattrjacobs/Hystrix,mickdwyer/Hystrix,eunmin/Hystrix,mickdwyer/Hystrix,ianynchen/Hystrix,mattrjacobs/Hystrix