Added MESOS-5763 to 0.28.3 CHANGELOG.

Added MESOS-5763 to 0.28.3 CHANGELOG.

Updated ticket names in CHANGELOG for 1.1.0.

Updated ticket names in CHANGELOG for 1.1.0.

Added MESOS-6457 to CHANGELOG for 1.1.0.

Added MESOS-6457 to CHANGELOG for 1.1.0.

Updated scheduler library to handle UUID parsing error.

Previously this would have thrown an exception.

Review: https://reviews.apache.org/r/52099

Added MESOS-5788 to 1.1.0 CHANGELOG.

Review: https://reviews.apache.org/r/53249/

Updated endpoint-help in preparation of 1.1.0.

Review: https://reviews.apache.org/r/52986/

Updated CHANGELOG for 1.0.2.