Changelog for v0.5.2 (2018-05-11):
* vendor/golang.org/x/text: Vendor collate and language
* hooks: Order injection by collated JSON filename
* libpod: Add HooksDirNotExistFatal
* hooks/read: Ignore IsNotExist for JSON files in ReadDir
* pkg/hooks: Version the hook structure and add 1.0.0 hooks
* Fix varlink remove image force
* Update Podman-specific readme
* Update main README
* vendor.conf: Pin containernetworking/plugins to 1fb94a42
* Do not error trying to remove cgroups that don't exist
* Remove parent cgroup we create with cgroupfs
* Place Conmon and Container in separate CGroups
* Add --cgroup-manager flag to Podman binary
* Major fixes to systemd cgroup handling
* Skip systemd-style CGroups test
* Alter CGroup path handling for 'podman top'
* Add validation for CGroup parents. Pass CGroups path into runc
* vendor/github.com/docker/docker/hack: Remove unused directory
* varlink info
* vendor.conf: Bump containerd/cgroups to 77e62851
* vendor.conf: Bump CNI to v0.6.0
* Dont eat the pull error message for varlink
* podman push should honor registries.conf
* alphabetize the varlink methods, types, and errors in the docs
* Add missing newline to podman port
* Generate varlink API documentation automatically
* Allow streaming on some varlink container methods
* Remove extra close from attach resize channel
* Vendor in latest containers/storage fix for UserNS
* container.go: fix lint error
* Dockerfile.Fedora: use fedora:28 instead of fedora:27
* Fix calculation of RunningFor in ps json output
* Should not error out if container no longer exists in oci
* Make invalid state nonfatal when cleaning up in run
* test/e2e/run_userns_test.go: new file
* podman, userNS: configure an intermediate mount namespace
* networking, userNS: configure the network namespace after create
* Begin wiring in USERNS Support into podman