Add a README section about contributing
Remove small optimization when parsing the input instruction.

Any instructions following INP were being ignored.
Fix instruction generation

Working well now.
Fix and improve LC3 compilation

Also improve Cargo.toml and add toasty LC3 VM primitives as dependency
main.rs is a test ground now, should be ignored.
Add reference to other LC3 projects
Improve cargo file, add README and license
Implement first PoC for LC3 backend
Tidy up code and prepare for LC3 backend
Add example programs
Implement initial prototype