Adds NewJWT

jwt.go

@@ -74,3 +74,7 @@ type TokenCreator func() interface{}
 func RegisterJwtType(ctx context.Context, generator TokenCreator) context.Context {
 	return context.WithValue(ctx, jwtKeyGenerator, generator)
 }
+
+func NewJWT(s jwt.Signer) *JWT {
+	return &JWT{signer: s}
+}