v0.4.0

Add support for VDLM2 messages. Since there is some overlap of common fields between the two message structures, we might go in a direction of combining and standardizing on a format that includes some or all of the fields from the different messages. As of now, they are separate but ACARS fields in VDLM2 match the corresponding ACARS field. One notable exception is vdlm2FrequencyHz, which is not in MHz like ACARS, but Hz.

New Environment Variables:

ACARSHUB_VDLM2_HOST: Host for ACARSHub instance distributing VDLM2 messages
ACARSHUB_VDLM2_HOST: Port for said instance
ANNOTATE_VDLM2: Whether or not to include annotated VDLM2 messages
VDLM2_ANNOTATOR_SELECTED_FIELDS: Which fields to include in the annotated data sent to receivers.

Full Changelog: v0.3.3...v0.4.0