- rename nonterminal (M)Ros2Rag to (M)RagConnect, and attribute ros2rag to ragconnect
- rename starter to safety
- make receiverstub, receiverstub not depend on safety
- make tests not depend on common (copied proto files)

- allow multiple mappings for update definitions
- in mappings, remove target variable name and prepare for more types, e.g., arrays
- add required option to specify name of root node in Compiler
- copy MqttUpdater in compile step

- renamed scanner and parser to Ros2Rag{Scanner,Parser}
- changed Compiler to not use System.exit throwing exceptions instead and have a dedicated run method
- implemented ASTNode.globallyResolveTokenComponentByToken and UpdateDefinition.resolveMappingByToken