Features:
 + {create,run}: add --no-new-keyring flag so that a new session keyring
   is not created for the container and the calling process's keyring is
   inherited.
 + restore: add --empty-ns flag to tell CRIU to only create a network
   namespace for a container and not populate it (allowing higher levels
   to correctly handle re-creating the network namespace).
 + {create,start}: use a FIFO rather than signals to signal the starting
   of a container. This removes the Go version restriction, and also
   avoids potential issues with Go's signal handling.
 + exec: allow additional groups to be overridden.
 + delete: add --force flag.
 - exec: disable the subreaper option entirely, because the option
   causes many issues with reparenting in the context of containers.
   This is not a complete fix, which is intended to land for -rc3. Using
   the removed option will be silently ignored by runC.
 + {create,run}: add support for masking directories with MaskPaths.
 + delete: allow for the deletion of multiple containers in one cmdline.
 + build: add `make release` for distributions.

Fixes:
 * Major improvements and fixes to CLI handling. Now commands like
   `runc ps` and `runc exec` will act sanely when you're trying to use
   flags that are not meant to be parsed by runC.
 * Set the cp.rt_* cgroup options correctly so that runC running in
   SCHED_RR (realtime) mode can operate properly.
 * Massive improvements to kmem limit detection to ensure that we only
   attempt to change memory.kmem.* if it is safe to do so.
 * Part of a major cleanup of the nsenter code, with more intended to
   land before -rc3.
 * Restored containers now have a start time, which is the time that the
   new container was started (not when the original container was
   started).
 * Fix the default cgroupPath behaviour, so that we actually attach to
   subcgroups of all of the caller's current cgroups (rather than using
   the devices cgroup path for all other cgroups)
 + Support 32bit UIDs on i386 with the setuid32(2) syscall.
 + Add /proc/timer_list to the set of default masked paths.
 - Do not create /dev/fuse by default.
 * Parse cgroupPath correctly if it contains ':'.
 * Add some more debugging information for the test suite, along with
   fixes for race conditions and other issues. In addition, add more
   integration tests for edge conditions.
 * Improve check-config.sh script to handle more cases.
 * Fix incorrect type when setting of net_cls classid.
 * Lots of fixes to help pages and man pages.
 + *: append -dirty to the version if the git repo is unclean.
 * Fix the JSON tags for CpuRt* options.
 * Cleanups to the rootfs setup code.
 * Improve error messages related to SELinux.

Thanks to all of the contributors that made this release possible:

 * Akihiro Suda <suda.akihiro@lab.ntt.co.jp>
 * Aleksa Sarai <asarai@suse.de>
 * Alexander Morozov <lk4d4math@gmail.com>
 * Andrew Vagin <avagin@virtuozzo.com>
 * Ben <ben.gray@bskyb.com>
 * Buddha Prakash <buddhap@google.com>
 * Carl Henrik Lunde <chlunde@ifi.uio.no>
 * Christian Brauner <cbrauner@suse.de>
 * Dam Thomason <ad@mthomason.net>
 * Dan Walsh <dwalsh@redhat.com>
 * Daniel, Dao Quang Minh <dqminh89@gmail.com>
 * Davanum Srinivas <davanum@gmail.com>
 * Euan Kemp <euank@coreos.com>
 * Guilherme Rezende <guilhermebr@gmail.com>
 * Haiyan Meng <hmeng@redhat.com>
 * Hushan Jia <hushan.jia@gmail.com>
 * Jiuyue Ma <majiuyue@huawei.com>
 * Johnny Bieren <jbieren@redhat.com>
 * Jonathan Boulle <jonathanboulle@gmail.com>
 * Justin Cormack <justin.cormack@docker.com>
 * Kenfe-Mickael Laventure <mickael.laventure@gmail.com>
 * Michael Crosby <crosbymichael@gmail.com>
 * Mike Brown <brownwm@us.ibm.com>
 * Mrunal Patel <mrunalp@gmail.com>
 * Peng Gao <peng.gao.dut@gmail.com>
 * Petar Petrov <pppepito86@gmail.com>
 * Phil Estes <estesp@linux.vnet.ibm.com>
 * Qiang Huang <h.huangqiang@huawei.com>
 * Serge Hallyn <serge@hallyn.com>
 * Seth Jennings <sjenning@redhat.com>
 * Shukui Yang <yangshukui@huawei.com>
 * Tristan Cacqueray <tdecacqu@redhat.com>
 * Vishnu kannan <vishnuk@google.com>
 * Wang Long <long.wanglong@huawei.com>
 * Yang Hongyang <imhy.yang@gmail.com>
 * Yen-Lin Chen <hencrice+FOSS@gmail.com>
 * Yuanhong Peng <pengyuanhong@huawei.com>
 * Zhang Wei <zhangwei555@huawei.com>
 * Zhao Lei <zhaolei@cn.fujitsu.com>
 * rajasec <rajasec79@gmail.com>
 * xiekeyang <xiekeyang@huawei.com>