This is in service to some submarine commits which will be arriving soon
to deal with Goodies templating. This makes UnixTime look "more like it
will" in addition to supplying what we determined to be the supplied
epoch.
This is most useful in the "empty" epoch case where we will tell them
the current epoch which may be of interest.
Disabling the no argument feature since:
- It triggers with just "time"
- The time shown doesn't follow the person's timezone (which is preferable over UTC)
There's no need to have a different Goodie to handle the "no remainder"
query case, so we'll just combine both into this single Goodie.
Also makes the goodie slightly more resilient against bad inputs by
`eval`ing all the way up through the DateTime creation and string
gathering.