Describe users rather than origin

[DanielOaks]

Rather than 'origin' being the useful bit of info, we should describe who uses the given mode/etc.

E.g. maybe something along these lines:

• Universal: Everyone uses this one.
• Universal except ...: When it's universal except a couple outliers.
• <list of software>: When it's less than almost-universal.

Esp for conflicts this'd be a lot better than the current state of only one impl listed for each with no way to tell how widespread one is over the other.