On the authzperf branch: Refactor the authz parser a wee bit.

* subversion/libsvn_repos/authz_parse.c
  (add_alias_definition, add_access_entry): New. Factored out from ...
  (rules_add_value): ... which is now much shorter and easier to understand.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/authzperf@1616390 13f79535-47bb-0310-9956-ffa450edef68