user: fix check for already existing user
user: fix fmt.Sprintf by actually placing a %s in the format string
user: check error on session save
lifelogd.conf: specify 32 bit sample keys
main: set the router as a global variable
main: name routes so we can reconstruct their urls later on
user: set the auth session cookie name as a constant
user: fix bug in row scan -- email comes after username
user: store the user id and username in the session cookie
user: lowercase passwordHash and passwordSalt so that they are not exported to consumers