Minor bug fixing

Allow implementation of Shader
Fix IndexOutOfBoundsException

Author: ZeroMemes

src/main/java/me/zero/client/api/util/render/RenderUtils.java

@@ -254,7 +254,7 @@ private static void rectangleGradient(float x1, float y1, float x2, float y2, in
             c1 = color[0];
             c2 = color[0];
             c3 = color[1];
-            c4 = color[2];
+            c4 = color[1];
         } else {
             c1 = color[0];
             c2 = color[1];

src/main/java/me/zero/client/api/util/render/gl/ShaderProgram.java

@@ -32,7 +32,7 @@
  * @author Brady
  * @since 7/23/2017 3:31 PM
  */
-public final class ShaderProgram extends GLObject {
+public class ShaderProgram extends GLObject {
 
     /**
      * Instance of the system supported shader adapter