Add an `integration` test group to Berksfile
Add an `integration` test group to Berksfile

These cookbooks are only required to drive the integration tests.
Sauraus/jenkins,eklein/jenkins,ebsco/jenkins,martinb3-cookbooks/jenkins,mknapik/jenkins,rchekaluk/jenkins,ryandub/jenkins,j-c-h-e-n-g/jenkins,samdunne/jenkins,ttab/jenkins,RSO/jenkins,daften/cookbook-jenkins,dshvedchenko/jenkins,StephenKing/chef-cookbook-jenkins,Sauraus/jenkins,cru-Luis-Rodriguez/jenkins,rapid7-cookbooks/jenkins,juliandunn/jenkins,Afterglow/jenkins,developerinlondon/jenkins,rapid7-cookbooks/jenkins,autoclone/jenkins,epu/epu-cb-jenkins,chef-cookbooks/jenkins,irccloud/jenkins,autoclone/jenkins-cookbook,pierreozoux/jenkins,duro/jenkins,juliandunn/jenkins,cru-Luis-Rodriguez/jenkins,epu/epu-cb-jenkins,Sauraus/jenkins,martinb3-cookbooks/jenkins,mlongob/jenkins,siteshwar/jenkins,gcymbalski/jenkins,rberger/jenkins,timops/jenkins,dekokun/jenkins,mknapik/jenkins,autoclone/iptables,mlongob/jenkins,Dispader/jenkins,jaredrussell/jenkins,AmoebaLabs/chef-jenkins,dshvedchenko/jenkins,samdunne/jenkins,schisamo/jenkins,Piousbox-cookbooks/jenkins,mknapik/jenkins,gshively11/jenkins,suchitpuri/jenkins,blt04/chef-jenkins,jhsubscribe/chef-jenkins,blackboard/jenkins,opscode-cookbooks/jenkins,autoclone/jenkins-cookbook,switchgears/jenkins,Dispader/jenkins,ebsco/jenkins,b-dean/jenkins,thrucker/jenkins,Tiger66639/jenkins,rexut/opscode-cookbooks-jenkins,rberrelleza/jenkins,erikthorselius/jenkins,team-lab/chef-jenkins,smedefind/jenkins,StephenKing/chef-cookbook-jenkins,umar85/jenkins,Piousbox-cookbooks/jenkins,RobertNorthard/jenkins,SinisterLight/jenkins,daften/cookbook-jenkins,samdunne/jenkins,uspeak/chef-jenkins,isbaran/jenkins,asmarre/jenkins,cburyta/jenkins,DanielRedOak/jenkins,mattjalexander/jenkins,autoclone/iptables,bencaron/jenkins,kippandrew/jenkins,martinb3-cookbooks/jenkins,rexut/opscode-cookbooks-jenkins,chef-cookbooks/jenkins,developerinlondon/jenkins,epu/epu-cb-jenkins,simplymeasured/opscode-cookbooks-jenkins,richleland/jenkins,streeter/jenkins,opscode-cookbooks/jenkins,rkolless/jenkins,b-dean/jenkins,rexut/opscode-cookbooks-jenkins,opscode-cookbooks/jenkins,rchekaluk/jenkins,krobertson/jenkins-cookbook,grigarr/jenkins,cru-Luis-Rodriguez/jenkins,mlongob/jenkins,ndobson/jenkins,daften/cookbook-jenkins,autoclone/jenkins,m1lth14d3s/jenkins,RobertNorthard/jenkins,Youscribe/jenkins-cookbook,developerinlondon/jenkins,autoclone/iptables,rchekaluk/jenkins,autoclone/jenkins-cookbook,ktc-itsnotbutter/jenkins,bhalothia/jenkins,rapid7-cookbooks/jenkins,dshvedchenko/jenkins,StephenKing/chef-cookbook-jenkins,kisoku/jenkins,crittercism/jenkins,j-c-h-e-n-g/jenkins,gshively11/jenkins,Da-Wei/jenkins,jcuzens/jenkins,rafaelmagu/jenkins,bhalothia/jenkins,umar85/jenkins,Dispader/jenkins,alex-slynko-wonga/jenkins,autoclone/jenkins,umar85/jenkins,streamlinesocial/jenkins,locke105/jenkins,j-c-h-e-n-g/jenkins,Piousbox-cookbooks/jenkins,chef-cookbooks/jenkins,Tiger66639/jenkins,RobertNorthard/jenkins,wanelo-chef/jenkins,mdlavin/jenkins,jbrehm/jenkins,Tiger66639/jenkins,priestjim/jenkins,ebsco/jenkins,bhalothia/jenkins,juliandunn/jenkins,hirocaster/jenkins-1,b-dean/jenkins,JeanMertz/jenkins-1,DataDog/jenkins,gshively11/jenkins,someara/jenkins-cookbook