Fixed issue thanhpd#13 (thanhpd#38)

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src/main/java/de/dennisguse/opentracks/introduction/IntroductionActivity.java

@@ -78,7 +78,7 @@ public Fragment createFragment(int position) {
                 return fc.newInstance();
             }
 
-            throw new RuntimeException("There isn't Fragment associated with the position: " + position);
+            throw new IllegalArgumentException("There isn't Fragment associated with the position: " + position);
         }
 
         @Override