update readme

Author: tiagoschenkel

README.md

@@ -10,7 +10,8 @@ RobotlegsJS Phaser-CE SignalCommandMap Extension
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-A RobotlegsJS Extension that allows the mapping of Phaser.Signal class to commands.
+A [RobotlegsJS](https://github.com/RobotlegsJS/RobotlegsJS) Extension that allows the mapping of
+[Phaser.Signal](https://photonstorm.github.io/phaser-ce/Phaser.Signal.html) class to commands.
 
 Installation
 ---