More dynamic creation of objects

ref #13

src/errors/GroupContactErrors.ts

@@ -0,0 +1,18 @@
+import { IsString } from 'class-validator';
+import { NotAcceptableError, NotFoundError } from 'routing-controllers';
+
+export class GroupContactWrongTypeError extends NotAcceptableError {
+	@IsString()
+	name = "GroupContactWrongTypeError"
+
+	@IsString()
+	message = "The groupContact must be either a existing groupContact, new groupContact or a existing adress's id. \n You provided a object of another type."
+}
+
+export class GroupContactNotFoundError extends NotFoundError {
+	@IsString()
+	name = "GroupContactNotFoundError"
+
+	@IsString()
+	message = "The groupContact you provided couldn't be located in the system. \n Please check your request."
+}