[ietf-dkim] Modified Introduction text forrfc4871-errata (resend)

[Murray S. Kucherawy]

> If you going to this level, you need to be more specific with software
> engineering terminologies and how it applies to SMTP.  Murray's API is
> not going to be same as MY API or that guys API and it may not be just
> in C or C++, but in multiple of languages, and the API be COM
> interface, a .NET interface,  including a JAVA interface.  It may come
> in the form of shims, hooks, callouts, triggers, events or what have
> you.

I don't think the proposed text defines any property of the API other than the fact that it must export two things: the verification result and the "d=" value.  The text does not stipulate what language has to be used, nor does it specify what that interface must look like.

So it already satisfies your requirement.