Fixed unittest for apache
Revert "Fixed unittest for apache"

This reverts commit 7b2935dfe95e5d86df166703c599b8e94978c96a.
Date parsing is only broken on my machine.
Added pull support for http

Implemented the client mode for the http input plugin.
This allows logstash to poll on a specific URL for log events.
You can use this to retrieve information from a status page
so that you get a sort of heartbeat from your system.

Also works well for systems that are not able to push events
to logstash over http.