Closed #140: The HEAD in ZooKeeper. Required yandex-sysmon/raava#24
Crutch with git_ for rules-api
HEAD link removed
Api accept HEAD via post-body
Fixed tests
Merge pull request #141 from mdevaev/head-in-zookeeper

Closed #140: The HEAD in ZooKeeper. Required yandex-sysmon/raava#24 (Review only!)
Removed except:raise
Version bump: v0.2