On the automatic-pager branch, enable the pager for 'svn log'.

* subversion/svn/log-cmd.c
  (svn_cl__log): Enable the pager in normal (non-XML) output mode.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/automatic-pager@1565017 13f79535-47bb-0310-9956-ffa450edef68