MSF: Support min significant figures instead of decimal places?

[naggie]

Imagine I have 2 disks, one 1TB and one 4TB, both 81% full.

With 0DP, the first will be represented with 5 characters, with decent precision :810GB
but the 4TB HDD used space would be represented with 3: 3TB which is not accurate enough (only 4 possible levels). I could add 1 or 2 decimal places, but then that would make the former unnecessarily long: 810.00GB. This isn't good for typography and space usage.

I think the solution would be min-significant-figures (MSF): the former would get 810GB and the latter, 43.24GB with a value of 2.

Do you agree?

Thanks for the library.