gnucash maint: Redefine some more buggy Guile string conversions.

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/c4e5e18c (commit)
	from  https://github.com/Gnucash/gnucash/commit/c4431607 (commit)



commit c4e5e18c0ad9e5848bd21684722d21a6ec6f9251
Author: John Ralls <jralls at ceridwen.us>
Date:   Tue Apr 24 17:57:52 2018 -0700

    Redefine some more buggy Guile string conversions.



Summary of changes:
 common/guile-mappings.h | 5 +++++
 1 file changed, 5 insertions(+)