Replace duplicate log tags


Check that AsyncRequestWorkerFactor is not negative

PR :54254
Submitted by: Jackie Zhang <jackie qq zhang gmail com>


remove unneeded include statements


Name pool + concat string at compile time when possible

* modules/filters/mod_ratelimit.c (rate_limit_filter): Log the error
  code.


Correct typo in error message
Submitted by: sf, jailletc36, jorton, jailletc36
Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1502204 13f79535-47bb-0310-9956-ffa450edef68