public static void enableConstraint(TableDescriptorBuilder builder,
    Class<? extends Constraint> clazz) throws IOException {
    changeConstraintEnabled(builder, clazz, true);
  }
Enable the given {@link Constraint}. Retains all the information (e.g. Configuration) for the
{@link Constraint}, but makes sure that it gets loaded on the table.
@param builder {@link TableDescriptorBuilder} to modify
@param clazz   {@link Constraint} to enable
@throws IOException If the constraint cannot be properly deserialized
hbase-server/src/main/java/org/apache/hadoop/hbase/constraint/Constraints.java