- only download bullet when its supposed to be built

jme3-bullet-native/build.gradle

@@ -132,10 +132,12 @@ unzipBullet.dependsOn {
 }
 
 compileJava.dependsOn {
+    if(buildNativeProjects=="true"){
         def bulletUnzipDir = new File(project.projectDir.absolutePath + File.separator + bulletFolder)
         if (!bulletUnzipDir.isDirectory()) {
             unzipBullet
         }
+    }
 }
 
 // Adds all available binaries to java jar task