Different application users of the writefreely pkg may want to set different log kinds of log messages for requests. We should add that ability in the Apper interface.
Add a new func to the Apper interface, e.g.
InfoLog(r *http.Request, status int, timeSince time.Duration) string
Then, use the result of this call as a parameter of the log.Info() call inside the deferred func inside all request handlers (in handle.go).
Use the current format as the implementation for the writefreely.App struct.