War on whitespace

This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time.  There are a few files that need
to have trailing whitespaces (most notably, test vectors).  The results
still passes the test, and build result in Documentation/ area is unchanged.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

mktag.c

@@ -11,7 +11,7 @@
  * The first three lines are guaranteed to be at least 63 bytes:
  * "object <sha1>\n" is 48 bytes, "type tag\n" at 9 bytes is the
  * shortest possible type-line, and "tag .\n" at 6 bytes is the
- * shortest single-character-tag line. 
+ * shortest single-character-tag line.
  *
  * We also artificially limit the size of the full object to 8kB.
  * Just because I'm a lazy bastard, and if you can't fit a signature