Support OS X 10.10 in "svn --version --verbose".

* subversion/libsvn_subr/sysinfo.c (release_name_from_version):
   Return the string "Yosemite" if the minor OS X version is 10.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1632898 13f79535-47bb-0310-9956-ffa450edef68