Support site monitor publisher

This publisher allows to check an URL after the build steps. It requires
the sitemonitor plugin from

https://wiki.jenkins-ci.org/display/JENKINS/SiteMonitor+Plugin

Change-Id: I83026e4db9bd7975a34b7d8e015a4a73c3b09ae8
Added support for Builds chain fingerprinter

Change-Id: I11429534a82587e7cbbd987ecce148b07a5ace47
Merge "Support site monitor publisher"