Add support for the NodeLabel Parameter plugin

Add support for using the NodeLabel Parameter plugin to
specify which node should run a job when triggering a
parameterized build.

Requires the Jenkins NodeLabel Parameter Plugin:
https://wiki.jenkins-ci.org/display/JENKINS/NodeLabel+Parameter+Plugin

Change-Id: Ie947a2a3069b477419db7eaa35307088712467e3
Add support for scripts in the inject builder

Sometimes we want to inject environment variables from
different sources, so it's very useful to be able to use
EnvInject's script parameters. This change adds support.

Change-Id: I5b3054c0fa8c5ba45fb3f73ed50a1da52f60fb8e
Support additional events for HipChat plugin

In newer versions, Jenkins HipChat plugin supports notifications for the
following events:

  notify-success
  notify-aborted
  notify-not-built
  notify-unstable
  notify-failure
  notify-back-to-normal

This commit adds support for these events in JJB. Also, introduces a
unit test for hipchat module and converts doc example generation to
literalinclude.

Change-Id: I3e09b4f2b41db58eb22ada89a633516e319a95bc
Merge "Add support for scripts in the inject builder"
Merge "Add support for the NodeLabel Parameter plugin"
Merge "Support additional events for HipChat plugin"