Several fixes to the "large dirs" benchmark:
Several fixes to the "large dirs" benchmark:

* tools/dev/benchmarks/large_dirs/create_bigdir.sh
  - add license header
  - allow for svnserve to use a different version as the client
  - actually delete the individual files - not the parent folder

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion