Fixed return type of #status()

ngprogress/ngprogress-tests.ts

@@ -6,10 +6,7 @@ var ngProgress: NgProgress.INgProgress = <any> {};
 ngProgress.start();
 ngProgress.height('10px');
 ngProgress.color('red');
-
-var statusResult: number = undefined;
-ngProgress.status();
-
+var statusResult: number = ngProgress.status();
 ngProgress.stop();
 ngProgress.set(50);
 ngProgress.reset();

ngprogress/ngprogress.d.ts

@@ -9,7 +9,7 @@ declare module NgProgress {
         start(): void;
         height(height: string): void;
         color(color: string): void;
-        status(): string;
+        status(): number;
         stop(): void;
         set(value: number): void;
         reset(): void;