Add support for the matrix-combinations plugin

This plugin allows a user to choose which matrix combinations
they want to run, as opposed to the default behaviour where
jenkins runs all combinations

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

Change-Id: I13205c81aa11523a4c3fc373820eb74863d0c7ca
Add perlcritic capability to violations method

Since new jenkins-violation plugin already have support for it
- https://wiki.jenkins-ci.org/display/JENKINS/Violations

Change-Id: Iad2c1fb5771322682d072cbe8183134994e83ac1
Merge "Add support for the matrix-combinations plugin"
Merge "Add perlcritic capability to violations method"