added functionality to get all routes between two nodes (fixed review comments)
added functionality to get all routes between two nodes (fixed review comments)

jonvestal/open-kilda,jonvestal/open-kilda,telstra/open-kilda,carmine/open-kilda,carmine/open-kilda,carmine/open-kilda,nikitamarchenko/open-kilda,carmine/open-kilda,nikitamarchenko/open-kilda,jonvestal/open-kilda,nikitamarchenko/open-kilda,nikitamarchenko/open-kilda,telstra/open-kilda,telstra/open-kilda,nikitamarchenko/open-kilda,jonvestal/open-kilda,telstra/open-kilda,telstra/open-kilda,nikitamarchenko/open-kilda,telstra/open-kilda,carmine/open-kilda,telstra/open-kilda,carmine/open-kilda,jonvestal/open-kilda