Merge pull request #9 from nikicat/master

pin elasticsearch-zookeeper version to 1.2.0
Merge pull request #10 from nikicat/master

dominator>=7 api migration
Merge pull request #11 from nikicat/master

migrated to dominator 8.1 api (log file support)
Merge pull request #12 from nikicat/master

migration to dominator >=9.1
Bump version: 1.4.0 → 1.5.0
fixed TextFile usage