Merge branch 'sb/dashless'

* sb/dashless:
  Make usage strings dash-less
  t/: Use "test_must_fail git" instead of "! git"
  t/test-lib.sh: exit with small negagive int is ok with test_must_fail

Conflicts:
	builtin-blame.c
	builtin-mailinfo.c
	builtin-mailsplit.c
	builtin-shortlog.c
	git-am.sh
	t/t4150-am.sh
	t/t4200-rerere.sh

index-pack.c

@@ -10,7 +10,7 @@
 #include "fsck.h"
 
 static const char index_pack_usage[] =
-"git-index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] [--strict] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
+"git index-pack [-v] [-o <index-file>] [{ ---keep | --keep=<msg> }] [--strict] { <pack-file> | --stdin [--fix-thin] [<pack-file>] }";
 
 struct object_entry
 {