Change documentation (issue #7)
This version introduces multiple enhancements:

All documentation changed to english language, and written missing documentation.
Also changed some code convention in the same files.

Details of additions/deletions below:
--------------------------------------------------------------

Modified:   /BLUE_FRAMEWORK/packages/disc/disc_class.php
            -- Modified --
               changed code conventions
               added documentation

Modified:   /BLUE_FRAMEWORK/packages/disc/file_class.php
            -- Modified --
               changed code conventions
               added documentation
            -- Added --
               some new empty functions, to future implement

Modified:   /BLUE_FRAMEWORK/packages/disc/folder_class.php
            -- Modified --
               changed code conventions
               added documentation
            -- Added --
               some new empty functions, to future implement