Update README.md

Author: HiddenMonk

README.md

@@ -1,7 +1,7 @@
 # Unity3DRuntimeTransformGizmo
 A runtime transform gizmo similar to unitys editor so you can translate (move, rotate, scale) objects at runtime.
 
-Video demonstration - https://www.youtube.com/watch?v=IUQqhS8tsNo
+Video demonstration - <a href="https://www.youtube.com/watch?v=IUQqhS8tsNo" target="_blank">https://www.youtube.com/watch?v=IUQqhS8tsNo</a>
 
 WARNING - There is a bug in unity 5.4 and 5.5 that causes InverseTransformDirection to be affected by scale which will break negative scaling. Not tested, but updating to 5.4.2 should fix it - https://issuetracker.unity3d.com/issues/transformdirection-and-inversetransformdirection-operations-are-affected-by-scale