title: error: package aurelienribon.tweenengine does not exist
body: <p>I set up the Project with LibGDX gradle and everything worked fine until i addet  Tween Engine Library to our libGDX projects</p>
  
  <p>my project convert from eclipse to android studio.</p>
  
  <p>My build.gradle looks like this :</p>
  
  <pre><code>android {
      buildToolsVersion "21.1.1"
      compileSdkVersion 21
      sourceSets {
          main {
              manifest.srcFile 'AndroidManifest.xml'
              java.srcDirs = ['src']
              aidl.srcDirs = ['src']
              renderscript.srcDirs = ['src']
              res.srcDirs = ['res']
              assets.srcDirs = ['assets']
              jniLibs.srcDirs = ['libs']
          }
  
          instrumentTest.setRoot('tests')
      }
  }
  // called every time gradle gets executed, takes the native dependencies of
  // the natives configuration, and extracts them to the proper libs/ folders
  // so they get packed with the APK.
  task copyAndroidNatives() {
      file("libs/armeabi/").mkdirs();
      file("libs/armeabi-v7a/").mkdirs();
      file("libs/x86/").mkdirs();
  
      configurations.natives.files.each { jar -&gt;
          def outputDir = null
          if (jar.name.endsWith("natives-armeabi-v7a.jar")) outputDir = file("libs/armeabi-v7a")
          if (jar.name.endsWith("natives-armeabi.jar")) outputDir = file("libs/armeabi")
          if (jar.name.endsWith("natives-x86.jar")) outputDir = file("libs/x86")
          if (outputDir != null) {
              copy {
                  from zipTree(jar)
                  into outputDir
                  include "*.so"
              }
          }
      }
  }
  task run(type: Exec) {
      def path
      def localProperties = project.file("../local.properties")
      if (localProperties.exists()) {
          Properties properties = new Properties()
          localProperties.withInputStream { instr -&gt;
              properties.load(instr)
          }
          def sdkDir = properties.getProperty('sdk.dir')
          if (sdkDir) {
              path = sdkDir
          } else {
              path = "$System.env.ANDROID_HOME"
          }
      } else {
          path = "$System.env.ANDROID_HOME"
      }
  
      def adb = path + "/platform-tools/adb"
      commandLine "$adb", 'shell', 'am', 'start', '-n', 'com.kilobolt.zombiebird.android/com.kilobolt.zombiebird.android.AndroidLauncher'
  }
  // sets up the Android Eclipse project, using the old Ant based build.
  eclipse {
      // need to specify Java source sets explicitely, SpringSource Gradle Eclipse plugin
      // ignores any nodes added in classpath.file.withXml
      sourceSets {
          main {
              java.srcDirs "src", 'gen'
          }
      }
  
      jdt {
          sourceCompatibility = 1.6
          targetCompatibility = 1.6
      }
  
      classpath {
          plusConfigurations += [project.configurations.compile]
          containers 'com.android.ide.eclipse.adt.ANDROID_FRAMEWORK', 'com.android.ide.eclipse.adt.LIBRARIES'
      }
  
      project {
          name = appName + "-android"
          natures 'com.android.ide.eclipse.adt.AndroidNature'
          buildCommands.clear();
          buildCommand "com.android.ide.eclipse.adt.ResourceManagerBuilder"
          buildCommand "com.android.ide.eclipse.adt.PreCompilerBuilder"
          buildCommand "org.eclipse.jdt.core.javabuilder"
          buildCommand "com.android.ide.eclipse.adt.ApkBuilder"
      }
  }
  // sets up the Android Idea project, using the old Ant based build.
  idea {
      module {
          sourceDirs += file("src");
          scopes = [COMPILE: [plus: [project.configurations.compile]]]
  
          iml {
              withXml {
                  def node = it.asNode()
                  def builder = NodeBuilder.newInstance();
                  builder.current = node;
                  builder.component(name: "FacetManager") {
                      facet(type: "android", name: "Android") {
                          configuration {
                              option(name: "UPDATE_PROPERTY_FILES", value: "true")
                          }
                      }
                  }
              }
          }
      }
  }
  dependencies {
      compile files('libs/tween-engine-api.jar')
      compile files('libs/tween-engine-api-sources.jar')
  }
  </code></pre>
  
  <p>error :</p>
  
  <pre><code>import aurelienribon.tweenengine.Tween;// error: package aurelienribon.tweenengine does not exist
  import aurelienribon.tweenengine.TweenEquations;//error: package aurelienribon.tweenengine does not exist
  import aurelienribon.tweenengine.TweenManager;//error: package aurelienribon.tweenengine does not exist
  </code></pre>
  
  <p>I really don't know what to do, i cant understand why this is happening.</p>