Avoid the wildcard import

Author: richardTingle

jme3-screenshot-tests/src/main/java/org/jmonkeyengine/screenshottests/testframework/TestDriver.java

@@ -50,7 +50,7 @@
 import javax.imageio.ImageWriteParam;
 import javax.imageio.ImageWriter;
 import javax.imageio.stream.ImageOutputStream;
-import java.awt.*;
+import java.awt.Color;
 import java.awt.image.BufferedImage;
 import java.io.IOException;
 import java.nio.file.Files;