The following consts MUST MATCH those defined in cmd/dotmesh-server/pkg/main/users.go FIXME: When we have a shared library betwixt client and server, we can put all this in there.

How many bytes of entropy in an API key.

4 hours.

And in a password hash.

And in a salt.

Scrypt parameters, these are considered good as of 2017 according to https://godoc.org/golang.org/x/crypto/scrypt.