<node/httpd conf> Bug 962938 - Set ProxyTimeout for node HTTPD config

Add ProxyTimeout setting to override server config default (picked up
from TimeOut, which is 60 in httpd.conf). Also add comment referencing
broker-specific setting for future reference.
Merge pull request #2485 from dobbymoodge/BZ962938-broker-proxytimeout

Merged by openshift-bot