Merge branch 'se/diff'

* se/diff:
  Convert some "apply --summary" users to "diff --summary".
  Add "--summary" option to git diff.

diff --cc diff.c
Simple merge

diff --cc diff.h
index bef586d8502f6e78b95cce15456704572ffe8c00,70077c6ed938848ba260672f8271a99ecfe9b0a3..3027974c1ec74217a58345b4ab48e673ee3db710
--- 1/diff.h
--- 2/diff.h
+++ b/diff.h
@@@ -31,8 -31,8 +31,9 @@@ struct diff_options 
                 binary:1,
                 full_index:1,
                 silent_on_remove:1,
-                find_copies_harder:1;
+                find_copies_harder:1,
+                summary:1;
 +      int context;
        int break_opt;
        int detect_rename;
        int line_termination;