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

builtin-init-db.c

@@ -354,7 +354,7 @@ static int guess_repository_type(const char *git_dir)
 }
 
 static const char init_db_usage[] =
-"git-init [-q | --quiet] [--bare] [--template=<template-directory>] [--shared[=<permissions>]]";
+"git init [-q | --quiet] [--bare] [--template=<template-directory>] [--shared[=<permissions>]]";
 
 /*
  * If you want to, you can share the DB area with any number of branches.