Fix review comments and new changes in config (#8515)

- Migrate and save only settings which are enabled
- Rename logger_http to logger_webhook and
  logger_http_audit to audit_webhook
- No more pretty printing comments, comment
  is a key=value pair now.
- Avoid quotes on values which do not have space in them
- `state="on"` is implicit for all SetConfigKV unless
  specified explicitly as `state="off"`
- Disabled IAM users should be disabled always

cmd/config/legacy.go

@@ -42,14 +42,13 @@ func SetRegion(c Config, name string) {
 
 // SetWorm - One time migration code needed, for migrating from older config to new for Worm mode.
 func SetWorm(c Config, b bool) {
+	if !b {
+		// We don't save disabled configs
+		return
+	}
 	// Set the new value.
 	c[WormSubSys][Default] = KVS{
-		State: func() string {
-			if b {
-				return StateOn
-			}
-			return StateOff
-		}(),
+		State:   StateOn,
 		Comment: "Settings for WORM, after migrating config",
 	}
 }