Release 0.17.3

# History

## 0.17.3

Install/update via the bootstrap script:

```shell
wget https://raw.githubusercontent.com/dokku/dokku/v0.17.3/bootstrap.sh
sudo DOKKU_TAG=v0.17.3 bash bootstrap.sh
```

### Bug Fixes

- #3570: @znz Fix typos in trace help

### New Features

- #3574: @josegonzalez Add support for pulling app status from scheduler plugins
- #3571: @znz Simplify hostname_regex

contrib/dokku-installer.py

@@ -10,7 +10,7 @@ import subprocess
 import sys
 import threading
 
-VERSION = 'v0.17.2'
+VERSION = 'v0.17.3'
 
 hostname = ''
 try: