Expanded stout::format() to handle 11 parameters.

From: Eric Biederman <ebiederm@xmission.com>
Review: https://reviews.apache.org/r/15013
Improved cgroups isolator to report additional memory statistics.

From: Eric Biederman <ebiederm@xmission.com>
Review: https://reviews.apache.org/r/15015
Fixed typos and errors in the Log Javadoc.
Added a note about the reliability of kill task requests.
Fixed typos in the Log javadoc.
Updated CHANGELOG for 0.15.0-rc4.
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