Adding the ability to retrieve the configured routes and default routes on Linux, *BSD and OS X systems.  *BSD related code was mostly guess work using examples of routing and some assumptions of similiar systems.  Definitely needs review for accuracy.  Also need to add Windows support.
lint
Fixing a typo in a comment for the netbsd specifc netstat route function.  adding an openbsd specific function, differs slightly from netbsd.
Merge pull request #17091 from garethgreenaway/network_routes

Adding network.route and network.default_route functions to network module.