Have startaws wait until instance starts

This would be a simple loop that checks to see if the result of `awsip` is null

Current output of startaws
```
{
"StartingInstances": [
{
"CurrentState": {
"Code": 0,
"Name": "pending"
},
"InstanceId": "there would be stuff here",
"PreviousState": {
"Code": 80,
"Name": "stopped"
}
}
]
}
```

New output
```
$ startaws large
Previous state: stopped
Current state: pending
Waiting...
Waiting...
Waiting...
Waiting...
Instance large started with ip "127.0.0.1"
```

Start with the `startaws` and `awsip` entry points, then run `startaws large` to observe the current behavior. Implement the requested wait until `awsip` returns an address, with status messages matching the example; done means the command reports the instance IP after it starts.

Written by the indexing model from the issue text.