Release notes:

• Bind mount ${NOMAD_ALLOC_DIR} into the container.
• Apply memory cgroups to the container.
• Add support for CPU shares
• Add host_dns flag into TaskConfig.
• Add option to select current working directory (cwd).
• Improve reliability by fixing issues. More details here
• Add commandline options so we can get the driver version via commandline via containerd-driver -v. Thanks to @lisongmin for the contribution.
• support volume_mount in the task. Thanks to @lisongmin for the contribution.
• Don't run CLA bot on comments.
• Remove network mbits from example jobs.
• Add a description for volume_mount stanza.