deploy: print last output line if no change in 10 seconds

Depends on #14. Merges #15.
If `deploy`'s output didn't change for 10 seconds, then print the last line of output to the chat.

```
Running 10 secs: <Last line of output>
Running 20 secs: <Last line of output>
Continuing...
```

You should probably remove deployment if it already has one. Or throw?
Otherwise you won't remove bindings.

Still not fan of storing callbacks on monitor itself, but we can live with that.