svn cleanup — 递归清理工作副本
Recursively clean up the working copy, removing working copy locks and
resuming unfinished operations.  If you ever get a working copy
locked error, run this command to remove stale locks and get your
working copy into a usable state again.
If, for some reason, an svn update fails due to a problem
running an external diff program (e.g., user input or network failure), pass
the --diff3-cmd to allow the cleanup process to complete
any required merging using your external diff program.  You can also specify
any configuration directory with the --config-dir option,
but you should need these options extremely infrequently.