Solely use datetime objects for timing

Also added some comments, and a different thing to write to logs when
commands are run. Oh and I changed a p to a u since it seems to contain a user object so u seemed to make more sense.
If you were going format-inception, you could do something like this:
```python
key_fmt = ["{0}"]
time_fmts = ["{{1[last{0}:%d/%m/%y %H:%M}}" for last in ("login", "logout")]
fmt = "/t/t".join(key_fmt + time_fmts)
```

Not recommended, though xD