default void setColumnSize(Integer columnSize) {
        put(HasColumnSizeUtil.COLUMN_SIZE, columnSize);
    }
Mutates the {@link HasColumnSize#getColumnSize() column size} of the
underlying document.

@param columnSize  the new column size (or {@code null}).
runtime-parent/runtime-config/src/main/java/com/speedment/runtime/config/mutator/trait/HasColumnSizeMutator.java