SunInfo: trim back location to two most specific bits
SunInfo: use less precise, but friendlier time.
SunInfo: wait until we're sure we have a DateTime to set tz.

We can eliminate the try, because once we've checked we have domething
in `$dt` it will be a DateTime. Presume we're smart enough to have
timezones in `$loc` which we can properly use.
SunInfo: create bizarre prose templating system.

Since I can't see what it looks like at the moment, I made it
crazy modular, extra emphasis on the crazy.