Error formatting names convention

[jsign]

In cmd/goal/messages.go I noticed that the error formatting strings don't follow a naming convention. Some of them prefix err, error, or suffix Error.

I'm not sure if there's the desired naming convention, which helps using hints while coding (e.g: since all errors start with err, and ide can hint existing errors). Possibly, this may apply to more places.

If that's the case, this could be tagged as an easy issue for someone to get involved in the code?

[howjmay]

May I take this issue and unite the suffix into err?

[Marcuccio]

It seems already closed, am I wrong?

[ian-algorand]

Thanks for the contribution!