Added routing table

main.go

protocols/bgp/packet/nlri.go

protocols/bgp/packet/path_attributes.go

protocols/bgp/packet/path_attributes_test.go

protocols/bgp/server/fsm.go

protocols/bgp/server/peer.go

protocols/bgp/server/server.go

rt/bgp.go

rt/client_manager.go

rt/filter.go

rt/route.go

rt/route_test.go

rt/routing_table.go

rt/routing_table_test.go

rt/static.go