public static long toLong(ByteBuffer buf, int offset) {
        if (LITTLE_ENDIAN) {
            return Long.reverseBytes(getAsLong(buf, offset));
        }
        return getAsLong(buf, offset);
    }
Reads a long value at the given buffer's offset considering it was written in big-endian
format.

@return long value at offset
stroom-bytebuffer/src/main/java/stroom/bytebuffer/hbase/UnsafeAccess.java