translate configuration (issue #100)

This version introduces multiple enhancements:

translated one of configuration variable name
removed all config descriptions from config.xml
changed variable name in libraries that use it

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

Modified:   /BLUE_FRAMEWORK/cfg/config.xml
            -- Updated --
                all configuration descriptions
            -- Removed --
                zmienne_rewrite_sep changed to var_rewrite_sep
Modified:   /BLUE_FRAMEWORK/packages/CORE/display_class.php
            -- Updated --
                _path changed configuration name
                _convert changed configuration name

Modified:   /BLUE_FRAMEWORK/packages/CORE/globals_class.php
            -- Updated --
                _modeRewrite changed configuration name

Modified:   /BLUE_FRAMEWORK/packages/CORE/lang_class.php
            -- Updated --
                _redirectWithLanguageCode changed configuration name