tests fail on trailing whitespace on osx

[sourcefrog]

At 76b9abc:

% make test
ccache cc -Wall -g -Werror   -c -o strnatcmp.o strnatcmp.c
ccache cc -Wall -g -Werror   -c -o natsort.o natsort.c
ccache cc -o natsort strnatcmp.o natsort.o
--- sorted-words    2015-06-05 18:41:31.000000000 -0700
+++ /dev/fd/63  2015-08-22 11:41:54.000000000 -0700
@@ -13,8 +13,8 @@
 pic3
 pic4
 pic 4 else
-pic 5
 pic 5 
+pic 5
 pic 5 something
 pic 6
 pic   7
Test failed for input file 'test-words'
make: *** [test] Error 1