Update utils.py

[jfmatth]

strftime doesn't allow for %s, but %S.

not sure what this is trying to do, but S fixes the issue.

[coveralls]

Coverage remained the same when pulling 237e9f1 on jfmatth:master into 80c5d80 on mishbahr:master.

[coveralls]

Coverage remained the same when pulling d33f24e on jfmatth:master into 80c5d80 on mishbahr:master.

[mishbahr]

return int(user.last_login.strftime('%S'))

won't work as it just returns second as a decimal number, I need the full timestamp. I pushed a fix for this issue. But THANK YOU again for your time and effort.