Py-osc2

* Update grammar to ASAM OpenSCENARIO DSL 2.1.0 public review draft:
* Add support for namespace mechanism
* Add support for extended floating point literals, including nan and inf
* Move to built-in indent-based lexer helper, add support for multi-line bracketed lists
* Enhance list of allowable keywords as identifiers

**Full Changelog**: https://github.com/PMSFIT/py-osc2/compare/v0.0.8...v0.1.0

* Fix grammar for variable field declarations to properly handle sample expressions, based on fixes in the OSC2 EBNF grammar.

**Full Changelog**: https://github.com/PMSFIT/py-osc2/compare/v0.0.7...v0.0.8