v1.3.1

Changes from 1.3.0 to 1.3.1

Fixed Issues:

• Fix kill service behavior by retrying forever
• Introduce UnknownTaskTerminatedEvent when a task is terminated and unknown.
• Add support for sentry.io by passing --sentry <url> and --sentry_tags tag1:value1,...
• Set a default exception handler
• Log error if invalid protobufs were in Zookeeper.
• Improve error message in start script if JAR is not found.
• Wait for tasks to be expunged
• Allow mesos container to run without cmd and args
• Fixes #4378 Replace $ with . in metric name
• Fixes #3957 Load previously stored health status when becoming leader.
• Ensure no new connections are accepted prior to closing out handlers.
• Document unit of disk space
• Fix dead link in native-docker.md
• Enhance docs for correct mesos credential usage.
• Add support for integration tests in velocity.
• Fixes #4202 - Run tests in parallel and disable a bunch of TaskKillServiceActorTests
  due to instability.
• Fix AuthorizedZooKeeperTest to not leak the client
• Call an optional start-book script from /bin/start
• Fixes #DCOS-9936 - Fix an occasional NPE in DeploymentActor
• Fixes #4269 - AppUpdate.empty was not persisting existing .upgradeStrategy or .residency
  so that app creation via PUT would override user entries with defaults.
• Fixes #4185 - Add documenting/protecting tests as well as a protecting test for .container