Refactor for 2.1.0

- All references to "bearing" changed to the more accurate "heading"
- ArtemisBearable removed; ArtemisOrientable now contains heading, pitch
and roll
- Pitch and roll added to player ships, NPC ships, and whales
- EliteAbility enum updated for Artemis 2.0
- Some unknown Bit enum value names changed to reflect byte and bit
numbers
- NpcUpdatePacket elite bits renamed
- Fixed incorrect default shield values for StationPacket
- Elite bits now spelled out in emitted property map
Added writing support for UnknownPacket
Added key capture packets

KeyCaptureTogglePacket, KeystrokePacket
Access updates

#9 Evaluate access
Merge pull request #18 from rjwut/2.1.0

Merging 2.1.0 into master