Print the error message for a aborted login in a new line (#229)

lib/login.js

@@ -55,7 +55,14 @@ function sleep(ms) {
 }
 
 async function register(url, {retryEmail = false} = {}) {
-  const email = await readEmail({invalid: retryEmail})
+  let email
+  try {
+    email = await readEmail({invalid: retryEmail})
+  } catch (err) {
+    process.stdout.write('\n')
+    throw err
+  }
+
   process.stdout.write('\n')
 
   if (!validate(email)) {