message: removed costly to lower and added regex for better time complexity
diff: @@ -166,12 +166,7 @@ class AlexaInteractionModel {
  throw new Error(errorPrefix + 'Invocation name must be between 2 and 50 characters.');
  }
  - if (alexaModel.interactionModel.languageModel.invocationName.toLowerCase() !==
  - alexaModel.interactionModel.languageModel.invocationName){
  - throw new Error(errorPrefix + 'Invocation name cannot contain upper case characters.');
  - }
  -
  - if(/\d/.test(alexaModel.interactionModel.languageModel.invocationName)){
  + if(/[A-Z0-9\d]/.test(alexaModel.interactionModel.languageModel.invocationName)){
  throw new Error(errorPrefix + 'Invocation name may only contain alphabetic characters, apostrophes, periods and spaces.');
  }
  