Fix bug: user name can't be empty.

git-svn-id: svn://bind10.isc.org/svn/bind10/trunk@1345 e5f2f494-b856-4b98-b285-d166d9295462

src/bin/usermgr/b10-cmdctl-usermgr.py.in

@@ -91,8 +91,12 @@ def main():
     try:
         while True :
             name = input("Desired Login Name:")
+            if name == '':
+                print("error, user name can't be empty")
+                continue
+
             if username_exist(name, filename):
-                 print("The usename already exist!")
+                 print("use name already exist!")
                  continue
 
             while True: