Close resource manager when host closes (#1343)
Close resource manager when host closes (#1343)

When a host is closed, it should close its resource manager.  Otherwise, goroutines are leaked.

Generally this is not a problem when a host exists for the life of a program, but can be a problem if hosts are created and closed.
ipfs/go-libp2p,libp2p/go-libp2p,libp2p/go-libp2p