[ Reverted in r1241040. ]
[ Reverted in r1241040. ]

Allocate mod_dav_svn's hook environment in a persistent pool. Fixes crashes.

* subversion/mod_dav_svn/mod_dav_svn.c
  (create_dir_config): The pool passed here doesn't have sufficient lifetime
   for the hook environment hash. So don't allocate it here.
  (merge_dir_config): Handle NULL hook environments in parent and child configs.
  (SVNHooksEnv_cmd): Allocate the hook environment hash table here. Make sure
   that all strings are allocated in the same pool as the hash table.

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