add system config (#71)

internal/config/systemdefaults/system_defaults.go

@@ -0,0 +1,12 @@
+package systemdefaults
+
+import "github.com/caos/zitadel/internal/crypto"
+
+type SystemDefaults struct {
+	SecretGenerator SecretGenerator
+}
+
+type SecretGenerator struct {
+	PasswordSaltCost      int
+	ClientSecretGenerator crypto.GeneratorConfig
+}