Update README.md

Author: fparismusic

README.md

@@ -139,8 +139,11 @@ Time expires before collecting all rings.
 
 ## Visual Preview
 ![Menu](images/1.png)
+*Figure 1: Game menu.*
 ![Drone at start](images/2.png)
+*Figure 2: Drone at start.*
 ![Flying drone with ring](images/3.png)
+*Figure 3: Flying drone with ring.*
 
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