Creating new file for alerts class

This class will be used for success/error messages in admin pages.
Created Alert Class

Created the MlwQmnAlertManager class. This class stores alerts in array
and then displays the alerts.
Replaced Old Error System With Alert Class

Replaced old error system with the new alert class.
Added Include Code For Alert Class
Use Of ob_start To Use Alerts

Had to put the tab contents inside ob_start to capture the newAlerts()
to display them above the tabs.
Replaced Error System With New Alert Class

Replaced the old error system we have been using since the beginning
with the new alert class.
Replaced Error System With Alert Class

Replaced the error system on this page with the new alert class.
Merge pull request #16 from fpcorso/feature/14

Created New Alert Manager Class