Correct readme example for product

[netei]

No description provided.

[cdax]

Hey @netei

Thanks for taking the time to validate the project documentation!

However, I tried running the script on the set of files shown in the README, and I'm not getting the results that you've shown in your PR. Am I missing something here?

[netei]

That's exactly what I get.

Here are the exact commands typed :

$ cat > set1.txt
abc
def
ghi
def
$ cat > set2.txt
def
ghi
ghi
abc
$ cat > set3.txt
abc
xyz
def
ghi
$ cat set
set1.txt  set2.txt  set3.txt
$ cat set*
abc
def
ghi
def
def
ghi
ghi
abc
abc
xyz
def
ghi
$ setop product set
set1.txt  set2.txt  set3.txt
$ setop product set1.txt set
set1.txt  set2.txt  set3.txt
$ setop product set1.txt set2.txt
ghi abc
def abc
abc abc
ghi def
def def
abc def
ghi ghi
def ghi
abc ghi
$

[netei]

up ?