Uniformity of TranspilationTrace and metamodels formats within StarLasu

[ftomassetti]

• Solve issue in Kolasu with TranspilationTrace serialization TranspilationTrace serialization does not work with origin and destination kolasu#128
• Save examples in StarLasu to be used as references Save examples of metamodels, AST models, and transpilation traces to use as references #10
• Regenerate examples of TranspilationTrace (https://github.com/Strumenta/transpiler-demo) and save them in Playground
• Document these formats Document transpilation trace and other EMF exported elements #12
• Rename metamodel from Kolasu to StarLasu in all projects (Kolasu: Rename metamodel from Kolasu V2 to StarLasu V2 kolasu#127)
• Update loading of transpilation traces in Tylasu Support last incarnation of transpilation traces tylasu#16

Implementation detail, not strictly required for this: #11

In the future, we should also implement support for saving transpilation traces in Pylasu.

As discussed in a meeting between @alessiostalla and @ftomassetti