Reduce the amount of benign logging

We went from not enough to too much :)

We now have a huge number of entries that look like this:

```
2017-04-07T15:57:41.319 Executing HTTP request: {
"requestId": "ec67f0fe-a629-4ed9-bd0c-8321d493b17d",
"method": "GET",
"uri": "/admin/host/status"
}
2017-04-07T15:57:41.366 Host Status: {
"id": "functiondevbignpm",
"state": "Running",
"version": "1.0.10841.0"
}
2017-04-07T15:57:41.366 Executed HTTP request: {
"requestId": "ec67f0fe-a629-4ed9-bd0c-8321d493b17d",
"method": "GET",
"uri": "/admin/host/status",
"authorizationLevel": "Admin"
}
2017-04-07T15:57:41.366 Response details: {
"requestId": "ec67f0fe-a629-4ed9-bd0c-8321d493b17d",
"status": "OK"
}
```

This is not ideal because:

- It make it harder to find important things
- It can weigh on the system, but via ETW and file system writes. When the portal is connected, the log files under `D:\home\LogFiles\Application\Functions\Host` grow pretty fast

We should dial it down, maybe by only logging error cases, which I think was what we needed to see when we didn't have enough logging.