Merge pull request #2 from nathan-gs/centos

Centos 6 support
Merge branch 'master' of https://github.com/wikimedia/puppet-cdh4
Zookeeper workaround: changed hostname to fqdn (more accurate)
Merge branch 'zookeeper'
Zookeeper workaround: updated the examples as well
Merge pull request #3 from nathan-gs/zookeeper

Zookeeper Ids
Modifying README
Merge branch 'master' of github.com:wikimedia/puppet-cdh4
Fixing examples/README.md
correct description and remove unneeded inline template
ensure config order is always the same or in some rubies output is rearanged (helpfully!) by zk
Merge pull request #4 from thattommyhall/master

zk tweaks
forgot .each after sort
Merge pull request #5 from thattommyhall/master

forgot .each after sort
MRv1 support: use it instead of YARN (both are NOT supported).
Merge pull request #9 from nathan-gs/mr1

MRv1 support: option to use it instead of YARN (both at the same time are NOT supported).
Merge remote-tracking branch 'wikimedia/master'