Bump version to 2.0.1

Bump version to 2.0.0

Bump version 1.1.4

Bump version to 1.1.3

Add circleci badge

Update rebar.config

Merge pull request #141 from waisbrot/rebar3

Update to use rebar3

Merge pull request #140 from chrzaszcz/master

Fix expected message format for the preparation_failed notification

Merge pull request #135 from matehat/new-status-codes

Updated Cassandra status codes

Bump version to 1.0.4