rewrite checkpoint

jiracli/keyring_windows.go

@@ -0,0 +1,11 @@
+package jiracli
+
+import "fmt"
+
+func keyringGet(user string) (string, error) {
+	return "", fmt.Errorf("Keyring is not supported for Windows, see: https://github.com/tmc/keyring")
+}
+
+func keyringSet(user, passwd string) error {
+	return fmt.Errorf("Keyring is not supported for Windows, see: https://github.com/tmc/keyring")
+}