[PATCH] lib: reword comment about XFOLDER: prefix

[David Bremner]

David Bremner <david at tethera.net> writes:

> I believe the current one is misleading, because in my experiments
> Xapian did not add : when prefix and term were both upper case. Indeed,
> it's hard to see how it could, because prefixes are added at a layer
> above Xapian in our code. See _notmuch_message_add_term for an example.
>
> Also try to explain why this is a good idea.  As far as I can ascertain,
> this is more of an issue for a system trying to work with an unknown set
> of prefixes. Since notmuch has a fixed set of prefixes, and we can
> hopefully be trusted not to add XGOLD and XGOLDEN as prefixes, it is
> harder for problems to arise.

pushed,

d