Allow users to specify the number of desired decimal places for the runtime seconds

[Rycieos]

Allowing users to specify the number of desired decimal places for the runtime seconds is desirable.

I would expect the most likely desired customization would be to have a configurable number of decimal places displayed for the seconds, but there may be people who also want something more exotic, like simply getting a decimal fraction of the biggest-involved unit, like:

• 58.23 seconds renders as "58.23s"
• 118.23 seconds renders as "1.97m"
• 7,128.23 seconds renders as "1.98h"
• 97,997.23 seconds renders as "1.13d"

Originally posted by @Magotchi in #790 (comment)