In svnserve, move the repository-specific data of the server
baton into a separate data structure.  Update a gazillion users.

This is the first in a series of commits attempting to separate
connection specific, repository specific and global data.  Once
that has been achieved, we can move towards suspendable sessions.
The latter is required when serving a (quasi) unlimited number
of connections through a limited number of threads.

* subversion/svnserve/server.h
  (authn_type,
   access_type): move up for future goodness
  (repository_t): factored out from ...
  (server_baton_t): ... this one

* subversion/svnserve/serve.c
  (log_server_error,
   log_command,
   log_authz_denied): update
  (canonicalize_access_file): only use the new repository_t
  (load_pwdb_config,
   load_authz_config, 
   authz_check_access,
   find_repos): update using an local variable
  (authz_check_access_cb_func,
   get_access,
   send_mechs,
   create_fs_access,
   auth,
   internal_auth_request,
   must_have_access,
   accept_report,
   reparent,
   get_latest_rev,
   get_dated_rev, 
   do_change_rev_prop),
   rev_proplist,
   rev_prop,
   add_lock_tokens,
   unlock_paths,
   commit,
   get_file,
   get_dir,
   update,
   switch_cmd,
   status,
   diff,
   get_mergeinfo,
   log_cmd,
   check_path,
   stat_cmd,
   get_locations,
   get_file_revs,
   lock,
   lock_many,
   unlock,
   unlock_many,
   get_lock,
   get_locks,
   replay_one_revision,
   replay_range,
   get_deleted_rev,
   get_inherited_props,
   get_normalized_repo_rel_path,
   get_revision_root): update
  (serve): ditto; update initialization code

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1529676 13f79535-47bb-0310-9956-ffa450edef68