public static byte[] padTail(final byte[] a, final int length) {
        byte[] padding = new byte[length];
        for (int i = 0; i < length; i++) {
            padding[i] = 0;
        }
        return add(a, padding);
    }
Make a new byte array from a subset of bytes at the tail of another, zero padded as desired.

@param a      array
@param length new array size
@return Value in <code>a</code> plus <code>length</code> appended 0 bytes
stroom-bytebuffer/src/main/java/stroom/bytebuffer/hbase/Bytes.java