* custom PMD ruleset which should have identical behavior to our previous default
* customize PMD rulesets
* exclude ExcessiveClassComplexity not ExcessiveClassLength
* also exclude ExcessiveClassLength
Merge branch 'master' of github.com:buttonmen-dev/buttonmen into 417_jenkins_pmd
Merge pull request #782 from cgolubi1/417_jenkins_pmd

jenkins pmd customization