Properly object oriented object pager

[jlbooker]

Create a properly object-oriented and pluggable data pagination system.

This should be able to page over any set of objects. One source of objects could be the database (phpws_db or Doctrine). Should probably also support "endless scrolling" method as well.

[Stardog]

Please review new Pager class.
https://github.com/AppStateESS/phpwebsite/blob/master/Global/Pager.php
https://github.com/AppStateESS/phpwebsite/blob/master/Global/DatabasePager.php
https://github.com/AppStateESS/phpwebsite/wiki/Pager