Add javadoc checkstyle

Author: patrickfav

checkstyle.xml

@@ -145,5 +145,13 @@
         <module name="RedundantImport"/> <!-- e.g. double import statements: http://checkstyle.sourceforge.net/config_imports.html#RedundantImport -->
         <module name="UnusedImports"/> <!-- http://checkstyle.sourceforge.net/config_imports.html#UnusedImports -->
         <module name="IllegalImport"/> <!-- checks if import sun.* is used http://checkstyle.sourceforge.net/config_imports.html#IllegalImport -->
+
+        <!-- Javadoc -->
+        <module name="JavadocType">
+            <property name="scope" value="protected"/> <!-- means protected and public -->
+        </module>
+        <module name="JavadocMethod">
+            <property name="scope" value="protected"/> <!-- means protected and public -->
+        </module>
     </module>
 </module>

src/main/java/at/favre/lib/bytes/BytesTransformers.java

@@ -171,6 +171,9 @@ public boolean supportInPlaceTransformation() {
      * Adds or converts to arbitrary checksum
      */
     public static final class ChecksumTransformer implements BytesTransformer {
+        /**
+         * Definitions of the mode
+         */
         public enum Mode {
             /**
              * Appends checksum to given byte array

src/main/java/at/favre/lib/bytes/Util.java

@@ -454,6 +454,12 @@ static boolean equals(byte[] obj, Byte[] anotherArray) {
      limitations under the License.
      =================================================================================================
      */
+
+    /**
+     * Class that calculates the entropy factor
+     *
+     * @param <T>
+     */
     static final class Entropy<T> {
         private final Map<T, Integer> map = new HashMap<>();
         private int total = 0;