Update CHANGELOG file bringing 0.9.0 in sync with JIRA.
MESOS-460: Remove LICENSE info from NOTICE: progress towards cleaning up LICENSE file too.
Fixed os::memory() and fs::available() to return Bytes.

Review: https://reviews.apache.org/r/10813
Fixed slave to use Bytes version of memory and disk.

Review: https://reviews.apache.org/r/10814
Fixed garbage collection to allow for disk head room.

Review: https://reviews.apache.org/r/10938
Fixed process isolator to safely setup launcher's environment.

Review: https://reviews.apache.org/r/10879
Fixed the resource monitor output upon collection failure.

Review: https://reviews.apache.org/r/10967
Updated post-reviews to work with the new git repository, by using
'master' instead of 'trunk'.

Review: https://reviews.apache.org/r/10968
Added the ability to install a failure signal handler, updated the
master and slave mains to do so.

Review: https://reviews.apache.org/r/10990
Changed the signal handler to use LOG(WARNING), corrected a comment.

Review: https://reviews.apache.org/r/10990
Updated post-reviews.py to use the correct apache git mirror.

Review: https://reviews.apache.org/r/11091
Fixed the MonitorTest by setting the timestamp of the
ResourceStatistics.

Review: https://reviews.apache.org/r/10715
Fixed libprocess to pipe all close()s through os::close().

Review: https://reviews.apache.org/r/11184
Fixed mesos to pipe all close()s through os::close().

Review: https://reviews.apache.org/r/11185
Fixed master to correctly terminate the non-checkpointing framework's
tasks, when a slave disconnects.

From: Brenden Matthews <brenden.matthews@airbnb.com>
Review: https://reviews.apache.org/r/11128
Upgraded libev to 4.15.

Review: https://reviews.apache.org/r/11289
Fixed python setup.py to use libev-4.15.

Review: https://reviews.apache.org/r/11290
Updated CHANGELOG.
Fixed scheduler driver to call disconnected() when master fails over.

Review: https://reviews.apache.org/r/11191
Fixed master to send a FrameworkReregistered message when the
framework re-registers with a failed over master.

Review: https://reviews.apache.org/r/11348