Remove unused files (issue #15)
This version introduces multiple enhancements:

Removed some unused files.

Details of additions/deletions below:
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Removed:   /BLUE_FRAMEWORK/data/data_class.php
           /BLUE_FRAMEWORK/data/simpleData_class.php
           /BLUE_FRAMEWORK/dataPresentation/tree_class.php
           /BLUE_FRAMEWORK/time/data_class.php
           /BLUE_FRAMEWORK/time/simpleData_class.php