[sprint] Use smarter parsing of some commands

[Laogeodritt]

Feedback 2: While it's efficient for people who are used to using it, the lack of words within certain commands makes it obfuscated to newbies. The bot I used during Nano is called Sprinto, and it accepts longer commands that are much more human readable. Kaz makes me type ".sprint start 20 5" but with Sprinto, I could type the equivalent of ".sprint start for 20 in 5" which makes much more sense to someone who doesn't already know the syntax. You can also rearrange it so you can just as easily say ".sprint start in 5 for 20" and get the same effect.