Implement publisher.checkstyle

Add publisher for Checkstyle Plugin[1] (based on code for the
Violations Plugin publisher)

[1] https://wiki.jenkins-ci.org/display/JENKINS/Checkstyle+Plugin

Change-Id: Ie622ad8600720081072f288e72dd56e65505380a
Reviewed-on: https://review.openstack.org/21066
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Approved: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Tested-by: Jenkins
Gitignore: Add /etc/jenkins_jobs.ini and output/ directory.

Change-Id: I358b0a05a2a1a9936f30eef3e77b555eff1044ec
Reviewed-on: https://review.openstack.org/21908
Reviewed-by: Khai Do <zaro0508@gmail.com>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins
Adding extended-choice functionality

This change adds the ability to use the extended choice plugin.
This plugin allows you to populate a file with choices and then
allow the user to select one or more when the build now button
is clicked.  This change only changes the properties and setup
files.

Change-Id: I05af63f75f9ab87cd923c23177d33898c26149cf
Reviewed-on: https://review.openstack.org/20610
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: Khai Do <zaro0508@gmail.com>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins
Fixing trigger-parameterized-builds example

The example for the trigger-parameterized-builds functionality is
incorrect.  A dash is needed before the project in the yaml so the
code knows that project is used multiple times.  I also added the
predefined-parameters value to the example to show how that is used,
 because it took me a while to figure out

Change-Id: Ib6c5ffb18c213ccc1396edd1264edbf4c28ff651
Reviewed-on: https://review.openstack.org/21129
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Khai Do <zaro0508@gmail.com>
Approved: Monty Taylor <mordred@inaugust.com>
Reviewed-by: Monty Taylor <mordred@inaugust.com>
Tested-by: Jenkins