Export, Streams, CharacterCodes, and BinaryIO

- [x] Implement  `Export`
- [x] Implement `RegisterExport`
- [x] Clean-up Stream handling
- [x] Implement `ToCharacterCode`
- [x] Implement `FromCharacterCode`
- [x] Implement `BinaryRead`
- [x] Implement  `BinaryWrite`
- [x] Add more Export formats