On the svnmucc branch, make 'install tools' idempotent.
* Makefile.in
(INSTALL_EXTRA_TOOLS): When creating a symlink, don't die if a file obstructs
it; instead, silently overwrite that file.
git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/svnmucc@1301151 13f79535-47bb-0310-9956-ffa450edef68