Atlas-2.2.1

New features:

1. Add ‘select/add/remove pwd(or enpwd)' command in admin interface, use this command to set the config option: pwds.
2. 'save config' command can save the pwds to the config file.
3. add ‘select version’ command in admin interface, use this command to show the version of Atlas.
4. log the forbidden SQLs and client ip to the log file.
5. close the inactive client connections after wait-timeout seconds.

Bug fix:

1. fix the bug of no checking the length of token which may lead Atlas crash.