Add "-scryptn" option that sets the cost parameter for scryptv0.5-rc1

Use that option to speed up the automated tests by 7 seconds.

Before:
	ok  	github.com/rfjakob/gocryptfs/integration_tests	26.667s
After:
	ok  	github.com/rfjakob/gocryptfs/integration_tests	19.534s

1 files changed, 1 insertions, 1 deletions

diff --git a/cryptfs/config_test.go b/cryptfs/config_test.go
index e052428..1c5a375 100644
--- a/cryptfs/config_test.go
+++ b/cryptfs/config_test.go
@@ -59,7 +59,7 @@ func TestLoadV2StrangeFeature(t *testing.T) {
 }
 
 func TestCreateConfFile(t *testing.T) {
-	err := CreateConfFile("config_test/tmp.conf", "test", false)
+	err := CreateConfFile("config_test/tmp.conf", "test", false, 0)
 	if err != nil {
 		t.Fatal(err)
 	}