## Issue Addressed
#1494
## Proposed Changes
- Give the TaskExecutor the sender side of a channel that a task can clone to request shutting down
- The receiver side of this channel is in environment and now we block until ctrl+c or an internal shutdown signal is received
- The swarm now informs when it has reached 0 listeners
- The network receives this message and requests the shutdown
## Issue Addressed
#1384
Only catch, as currently implemented, when dialing the multiaddr nodes, there is no way to ask the peer manager if they are already connected or dialing
