Make full example modules (issue #20)

This version introduces multiple enhancements:

finished example with navigation, also rebuilded breadcrumbs module

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

Added:      /BLUE_FRAMEWORK/modules/example_navigation/example_navigation.php
            -- Added --
                main example script

Added:      /BLUE_FRAMEWORK/modules/example_navigation/layouts/index.html
            -- Added --
                main example template

Added:      /BLUE_FRAMEWORK/modules/example_navigation/lang/example_navigation_pl-PL.php
            -- Added --
                polish translations

Added:      /BLUE_FRAMEWORK/modules/example_navigation/lang/example_navigation_en-GB.php
            -- Added --
                english translations

Modified:   /BLUE_FRAMEWORK/cfg/lang/core_pl-PL.php
            -- Added --
                example list polish description

Modified:   /BLUE_FRAMEWORK/cfg/lang/core_en-GB.php
            -- Added --
                example list english description

Modified:   /BLUE_FRAMEWORK/elements/layouts/examples/examples.html
            -- Added --
                description marker

Modified:   /BLUE_FRAMEWORK/cfg/tree.xml
            -- Added --
                example_navigation page

Modified:   /BLUE_FRAMEWORK/modules/main/main.php
            -- Added --
                breadcrumbsAdvanced method to return ready breadcrumb
            -- Updated --
                run to handle breadcrumbsAdvanced