Update error message now that --dev is default

Fixes #1970.

src/Composer/Package/Locker.php

@@ -100,7 +100,7 @@ class Locker
             if (isset($lockData['packages-dev'])) {
                 $lockedPackages = array_merge($lockedPackages, $lockData['packages-dev']);
             } else {
-                throw new \RuntimeException('The lock file does not contain require-dev information, run install without --dev or run update to install those packages.');
+                throw new \RuntimeException('The lock file does not contain require-dev information, run install with the --no-dev option or run update to install those packages.');
             }
         }