Firecracker v0.19.0

Added

• New command-line parameter for firecracker, named --no-api, which
  will disable the API server thread. If set, the user won't be able to send
  any API requests, neither before, nor after the vm has booted. It must be
  paired with --config-file parameter. Also, when API server is disabled,
  MMDS is no longer available now.
• New command-line parameter for firecracker, named --config-file, which
  represents the path to a file that contains a JSON which can be used for
  configuring and starting a microVM without sending any API requests.
• The jailer adheres to the "end of command options" convention, meaning
  all parameters specified after -- are forwarded verbatim to Firecracker.
• Added KVM_PTP support to the recommended guest kernel config.
• Added entry in FAQ.md for Firecracker Guest timekeeping.

Changed

• Vsock API call: PUT /vsocks/{id} changed to PUT /vsock and no longer
  appear to support multiple vsock devices. Any subsequent calls to this API
  endpoint will override the previous vsock device configuration.
• Removed unused 'Halting' and 'Halted' instance states.

Fixed

• Fixed serial console on aarch64 (GitHub issue #1147).
• Upon panic, the terminal is now reset to canonical mode.
• Explicit error upon failure of vsock device creation.
• The failure message returned by an API call is flushed in the log FIFOs.
• Insert virtio devices in the FDT in order of their addresses sorted from
  low to high.
• Enforce the maximum length of the network interface name to be 16 chars as
  specified in the Linux Kernel.
• Changed the vsock property id to vsock_id so that the API client can be
  successfully generated from the swagger definition.