We use bcrypt hashes for password storage, but the principle is the same.
I've created a simple script that will create a hash in the required format for you.
https://gist.github.com/dennis-learningpool/4a4a9c01017bc9640478
If you download that script and pop it into the root of your adapt_authoring project, you can then generate a hash with the command:
node passwordgen.js mypassword
The output hash string can then be added directly to the record via robomongo.