Added fixtures to enable templatized isolation module tests
and fixed a bug in cgroups isolation module.

Review: https://reviews.apache.org/r/9847

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1455809 13f79535-47bb-0310-9956-ffa450edef68
Added status update manager.

Review: https://reviews.apache.org/r/7212

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1455810 13f79535-47bb-0310-9956-ffa450edef68
Integrated status update manager into the slave.

Review: https://reviews.apache.org/r/7655

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1455811 13f79535-47bb-0310-9956-ffa450edef68
Checkpointed slave, framework, executor and tasks.

Review: https://reviews.apache.org/r/8535

git-svn-id: https://svn.apache.org/repos/asf/incubator/mesos/trunk@1455812 13f79535-47bb-0310-9956-ffa450edef68