users: rename createdAt to creationTime

src/users.js

@@ -154,7 +154,7 @@ function create(username, password, email, displayName, options, auditSource, ca
     const source = options.source || '';        // empty is local user
     const role = options.role || exports.ROLE_USER;
 
-    var error;
+    let error;
 
     if (username !== null) {
         username = username.toLowerCase();
@@ -185,15 +185,13 @@ function create(username, password, email, displayName, options, auditSource, ca
         crypto.pbkdf2(password, salt, CRYPTO_ITERATIONS, CRYPTO_KEY_LENGTH, CRYPTO_DIGEST, function (error, derivedKey) {
             if (error) return callback(new BoxError(BoxError.CRYPTO_ERROR, error));
 
-            var now = (new Date()).toISOString();
-            var user = {
+            const user = {
                 id: 'uid-' + uuid.v4(),
                 username: username,
                 email: email,
                 fallbackEmail: email,
                 password: Buffer.from(derivedKey, 'binary').toString('hex'),
                 salt: salt.toString('hex'),
-                createdAt: now,
                 resetToken: '',
                 displayName: displayName,
                 source: source,