v0.3.0

This is the massive refactoring release: all internal and external interfaces has been changed; also the tool stability has been greatly improved.

Improvements:

• Refactor error handling (#53)
• Reliable extraction of counterexample traces (#58)
• Reintroduce generic artifacts (#61)
• Rework Apalache module (#62)
• Rework TLC module (#63)

Bug fixes:

• Confusing "No test trace found" error state (#52)
• Running binary with only the argument tla causes panic instead of giving warning to user (#55)
• Translate.tla counterexample using modelator tla tla-trace-to-json-trace results in parsing error (#56)