fix bug - can not update Email-ssmtp if user deleted
fix bug - can not update Email-ssmtp if user deleted

Traceback (most recent call last):
  File "zabbix-ldap-sync", line 868, in <module>
    main()
  File "zabbix-ldap-sync", line 865, in main
    config.media_opt)
  File "zabbix-ldap-sync", line 638, in sync_users
    sendto = ldap_conn.get_user_media(ldap_users[eachUser], ldap_media)
KeyError: u'allburov'

allburov/zabbix-ldap-sync,dnaeon/zabbix-ldap-sync