Fixed GammaCorrectionFilter path to j3md and frag files

jme3-effects/src/main/java/com/jme3/post/filters/GammaCorrectionFilter.java

@@ -64,7 +64,7 @@ public class GammaCorrectionFilter extends Filter {
     @Override
     protected void initFilter(AssetManager manager,
             RenderManager renderManager, ViewPort vp, int w, int h) {
-        material = new Material(manager, "Materials/Filter/GammaCorrection.j3md");
+        material = new Material(manager, "Common/MatDefs/Post/GammaCorrection.j3md");
         material.setFloat("InvGamma", 1.0f/gamma);        
     }
 

jme3-effects/src/main/resources/Common/MatDefs/Post/GammaCorrection.j3md

@@ -8,7 +8,7 @@ MaterialDef GammaCorrection {
  
     Technique {
         VertexShader GLSL150:   Common/MatDefs/Post/Post15.vert
-        FragmentShader GLSL150: Materials/Filter/GammaCorrection15.frag
+        FragmentShader GLSL150: Common/MatDefs/Post/GammaCorrection15.frag
  
         WorldParameters {
         }
@@ -20,7 +20,7 @@ MaterialDef GammaCorrection {
  
     Technique {
         VertexShader GLSL100:   Common/MatDefs/Post/Post.vert
-        FragmentShader GLSL100: Materials/Filter/GammaCorrection.frag
+        FragmentShader GLSL100: Common/MatDefs/Post/GammaCorrection.frag
  
         WorldParameters {
         }