simple eprintln fixes

[Crypto-Spartan]

I found 2 instances where ouch should be using eprintln instead of println and fixed them here.

[marcospb19]

Have you reviewed all the usages of println and eprintln?

We had discussions previously about where output should be directed to, and then stuff changed, I think that these eprintln were left from previous decisions.

[Crypto-Spartan]

I saw the issues with the discussion, notably #110 & #114.

The discussions in those issues talked about moving all output to stderr, even normal [INFO] outputs. In the 2 instances I changed, they should have been directed to stderr in the first place (since they were actual errors) but they were going to stdout instead. So this PR shouldn't have any impact on the other issues, AFAIK.

I believe that I reviewed all of the usages of print, println, & eprintln, but there is a chance that I missed one somewhere.