Added custom errors

ref #4 #5

src/errors/TrackErrors.ts

@@ -0,0 +1,18 @@
+import { JsonController, Param, Body, Get, Post, Put, Delete, NotFoundError, OnUndefined, NotAcceptableError } from 'routing-controllers';
+import { IsInt, IsNotEmpty, IsPositive, IsString } from 'class-validator';
+
+export class TrackNotFoundError extends NotFoundError {
+	@IsString()
+	name = "TrackNotFoundError"
+
+	@IsString()
+	message = "Track not found!"
+}
+
+export class TrackIdChangeNotAllowedError extends NotAcceptableError {
+	@IsString()
+	name = "TrackIdChangeNotAllowed"
+
+	@IsString()
+	message = "The id's don't match!!"
+}