writeByte() may be improved for byte array based BufferedData

[artemananiev]

ByteArrayBufferedData.writeByte() method looks like this:

    public void writeByte(final byte b) {
        validateCanWrite(1);
        final int pos = buffer.position();
        array[arrayOffset + pos] = b;
        buffer.position(pos + 1);
    }

Besides putting the byte to the byte array, it has a check and two calls to buffer.position() When multiple bytes are written one by one, this overhead becomes noticeable. For example, this writeByte() method is used in Utf8Tools, which is used to write all strings.