Code + comment cleanup for the response models

ref #39

src/models/responses/ResponseTrack.ts

@@ -1,16 +1,12 @@
-import {
-    IsInt,
-
-    IsString
-} from "class-validator";
+import { IsInt, IsString } from "class-validator";
 import { Track } from '../entities/Track';
 
 /**
- * Defines a track of given length.
+ * Defines the track response.
 */
 export class ResponseTrack {
     /**
-     * Autogenerated unique id (primary key).
+     * The track's id.
      */
     @IsInt()
     id: number;;
@@ -27,6 +23,10 @@ export class ResponseTrack {
     @IsInt()
     distance: number;
 
+    /**
+     * Creates a ResponseTrack object from a track.
+     * @param track The track the response shall be build for.
+     */
     public constructor(track: Track) {
         this.id = track.id;
         this.name = track.name;