[PATCH] cli/new: improve error reporting

[David Bremner]

David Bremner <david at tethera.net> writes:

> Recently a user reported a crash in notmuch new, but because of
> missing error reporting, all they could say was "A Xapian exception
> occured". This commit adds the extra information available about
> the error message in the exception.

pushed to master. Actually, I think another user reported the unhelpful
xapian exception recently.

d