MATH-1524: Add package-info.java file in package initialization.

src/main/java/org/apache/commons/math4/ml/clustering/initialization/package-info.java

@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/**
+ * Clusters Initialize methods.
+ *
+ * All centroid cluster initializer should implement the
+ * {@link org.apache.commons.math4.ml.clustering.initialization.CentroidInitializer}
+ * interface.
+ */
+package org.apache.commons.math4.ml.clustering.initialization;