public static String alignCenter(String substring, int totalWidth) {
        return alignCenter(substring, totalWidth, ' ');
    }
Returns a string of the specified length where the substring is located
in the middle, padded with spaces on both sides. If uneven, an extra
space will be added to the right side. If the specified 
{@code totalWidth} is less than the length of the substring, the
substring is returned but with the overflowing characters removed.

@param substring   the substring to align
@param totalWidth  the width of the returned string
@return            the padded string
common-parent/codegen/src/main/java/com/speedment/common/codegen/internal/util/TextUtil.java