added mesos module, more tests
Squashed 'library/zookeeper/' content from commit a3a9c7a

git-subtree-dir: library/zookeeper
git-subtree-split: a3a9c7abf901f262b1898b7652d1f031a5fc0b8f
Merge commit '55bd781aa3b676d0222c2830b1e3f4714532e068' as 'library/zookeeper'
remove zookeeper module
moved mesos_facts to its open repo