Update jenkins

Official image repository has been moved to jenkinsci github account
+ minor fix

library/jenkins

@@ -1,6 +1,6 @@
 # maintainer: Nicolas De Loof <[email protected]> (@ndeloof)
 # maintainer: Michael Neale <[email protected]> (@michaelneale)
 
-latest: git://github.com/cloudbees/jenkins-ci.org-docker@66dc63923438e70eaebd68da41bc7b9ea35ce2aa
-1.596.2: git://github.com/cloudbees/jenkins-ci.org-docker@66dc63923438e70eaebd68da41bc7b9ea35ce2aa
+latest: git://github.com/jenkinsci/jenkins-ci.org-docker@8f909abee98247ad482efb6d21833e2054e3e9de
+1.596.2: git://github.com/jenkinsci/jenkins-ci.org-docker@8f909abee98247ad482efb6d21833e2054e3e9de