On the log-message-templates branch, support log templates during
commit operations which don't use a working copy.

* subversion/include/svn_client.h
  (svn_client_get_log_message_templates): Update declaration and docstring.

* subversion/libsvn_client/commit_util.c
  (svn_client_get_log_message_templates): Support URLs as well as paths.
  (svn_client__get_log_msg): Pass paths and URLs to
   svn_client_get_log_message_templates().

Suggested by: rhuijben


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/log-message-templates@1622710 13f79535-47bb-0310-9956-ffa450edef68