Fix for issue 134

[GlenKelley]

Fixes #134

This changes the behaviour from:

>formatPrefix("(~s", 1e3)(-1e3)`
(1)k

To be:

>formatPrefix("(~s", 1e3)(-1e3)`
(1k) 

A side effect of this change is we now include the unit to be included in the padding length, e.g:

>formatPrefix("(~s", 1e3)(-1e3)`
      −$42.0M

Becomes:

>formatPrefix("(~s", 1e3)(-1e3)`
     −$42.0M

[treloar]

👍

[declanjscott]

👍 thanks for this!

[GlenKelley]

Note it would be cleaner if this was supported by the formatSpecifier, but that would require extending the format regex to support fixed suffix strings.

[GlenKelley]

@mbostock What is the process for getting this change approved+merged?

[mbostock]

I’ll get to it eventually. I appreciate your patience.