[PATCH] go: use a different goconfig package

[David Bremner]

Justus Winter <4winter at informatik.uni-hamburg.de> writes:

> The notmuch-addrlookup utility uses a third party library to read the
> notmuch configuration file. The previously used implementation at
> "github.com/kless/goconfig" vanished, so this patch switches to the
> implementation at "github.com/msbranco/goconfig". As the
> implementations differ at the API level, the code is updated
> accordingly.

Pushed,

d