t / t4135 / add-with quote.diffon commit hash.h: move SHA-1 implementation selection into a header file (f18f816)
   1diff -pruN a/"postimage".txt b/"postimage".txt
   2--- a/"postimage".txt   1969-12-31 18:00:00.000000000 -0600
   3+++ b/"postimage".txt   2010-08-18 20:13:31.756002255 -0500
   4@@ -0,0 +1 @@
   5+postimage