gnucash maint: un_escape: More terse, more correct.

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/127c658f (commit)
	from  https://github.com/Gnucash/gnucash/commit/f2976420 (commit)



commit 127c658f05afd4bdddfdd0c04d02aa7fd9264c76
Author: John Ralls <jralls at ceridwen.us>
Date:   Wed Dec 19 22:35:18 2018 -0800

    un_escape: More terse, more correct.
    
    Doesn't run past the end of the input string even if the last
    character is a quote.



Summary of changes:
 gnucash/import-export/bi-import/dialog-bi-import.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)