Refactor TypeManager - remove unnecessary add() method from interface allowing it to be private

ebean-core/src/main/java/io/ebeaninternal/server/type/DefaultTypeManager.java

@@ -159,8 +159,7 @@ public final class DefaultTypeManager implements TypeManager {
   /**
    * Register a custom ScalarType.
    */
-  @Override
-  public void add(ScalarType<?> scalarType) {
+  private void add(ScalarType<?> scalarType) {
     typeMap.put(scalarType.type(), scalarType);
     logAdd(scalarType);
   }

ebean-core/src/main/java/io/ebeaninternal/server/type/TypeManager.java

@@ -11,11 +11,6 @@ import java.lang.reflect.Type;
  */
 public interface TypeManager {
 
-  /**
-   * Register a ScalarType with the system.
-   */
-  void add(ScalarType<?> scalarType);
-
   /**
    * Return the scalar type for the given logical type.
    */