Squashed commit of the following:

commit 706afabff19a69aca0abd17ee9dc8ad3d295d6f6
Author: Saulo Aguiar <sauloaguiar89@gmail.com>
Date:   Mon Apr 29 21:16:55 2013 -0300

    DatabaseDevelopment

    Description: Functions for querying intervals

    	Adding function to get Checkins from a specific day
    	Adding function to get Checkins from a specified interval
    	Adding InvalidOrderException to notify when order date was wrong

    Commit: Add

    TaskNumber: #2
Merge branch 'master' of https://github.com/androidzin/ponto-pro