style(error): order ERRNO constant numerically
style(error): order ERRNO constant numerically

Closes #1518 
mozilla/fxa-auth-server,mozilla/fxa-auth-server,eoger/fxa-auth-server,eoger/fxa-auth-server,eoger/fxa-auth-server,eoger/fxa-auth-server,mozilla/fxa-auth-server,mozilla/fxa-auth-server