Warn on key file parse errors, rather than explode
Warn on key file parse errors, rather than explode

Contrary to popular belief, it is possible to encounter errors when parsing
key files. In this case, the key-file backend shouldn't explode without a
helpful error message. Helps: bgo#628930

pwithnall/folks,renatofilho/folks2,renatofilho/folks2,GNOME/folks,renatofilho/folks2,renatofilho/folks,renatofilho/folks,renatofilho/folks,pwithnall/folks,GNOME/folks,renatofilho/folks2,GNOME/folks,pwithnall/folks,renatofilho/folks