Introduce test for DEBUG_CACHE_DUMP_STATS preprocessor macro / definition to enable dumping cache statistics to console upon the end of the FSFS session.
Introduce test for DEBUG_CACHE_DUMP_STATS preprocessor macro / definition
to enable dumping cache statistics to console upon the end of the FSFS session.

* subversion/libsvn_fs_fs/caching.c
  (dump_cache_baton_t, dump_cache_statistics): new function & parameter
  (init_callbacks): register the new callback, if configured at compile time

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