code: private void addPropertiesAtPath(
        Map<String, Object> existingProperties, PropDeclarationContext prop) throws ParseException{
      addPropertiesAtPath(prop, existingProperties, prop.path, parsePropValue(prop));
    }
docs: Adds additional properties to an existing properties map at the location identified by
  the given PropDeclarationContexts path.
  
  @param existingProperties provides the existing properties to add the additional properties to.
  @param prop provides the ANTLR property AST node to add the properties for.