tweaks to backup & verifydata tool to make a typical backup+verifydata produce no output

for easy use in a crontab

backup.go

@@ -509,9 +509,6 @@ func backupctl(ctx context.Context, ctl *ctl) {
 		}
 		p := srcpath[len(srcDataDir)+1:]
 		if p == "queue" || p == "acme" || p == "tmp" {
-			if p == "tmp" {
-				xwarnx("skipping entire tmp directory", nil, mlog.Field("path", p))
-			}
 			return fs.SkipDir
 		}
 		l := strings.Split(p, string(filepath.Separator))

doc.go

@@ -352,8 +352,8 @@ specifically mounts the data directory, causing attempts to hardlink outside it
 to fail with an error about cross-device linking.
 
 All files in the data directory that aren't recognized (i.e. other than known
-database files, message files, an acme directory, etc), are stored, but with a
-warning.
+database files, message files, an acme directory, the "tmp" directory, etc),
+are stored, but with a warning.
 
 A clean successful backup does not print any output by default. Use the
 -verbose flag for details, including timing.

main.go

@@ -983,8 +983,8 @@ specifically mounts the data directory, causing attempts to hardlink outside it
 to fail with an error about cross-device linking.
 
 All files in the data directory that aren't recognized (i.e. other than known
-database files, message files, an acme directory, etc), are stored, but with a
-warning.
+database files, message files, an acme directory, the "tmp" directory, etc),
+are stored, but with a warning.
 
 A clean successful backup does not print any output by default. Use the
 -verbose flag for details, including timing.

verifydata.go

@@ -335,13 +335,13 @@ possibly making them potentially no longer readable by the previous version.
 	checkAccounts()
 	checkOther()
 
-	if fail {
-		log.Fatalf("errors were found")
-	} else {
-		log.Printf("%s: OK", dataDir)
-	}
-
 	if backupmoxversion != moxvar.Version {
 		log.Printf("NOTE: The backup was made with mox version %q, while verifydata was run with mox version %q. Database files have probably been modified by running mox verifydata. Make a fresh backup before upgrading.", backupmoxversion, moxvar.Version)
 	}
+
+	if fail {
+		log.Fatalf("errors were found")
+	} else {
+		fmt.Printf("%s: OK\n", dataDir)
+	}
 }