XD-2239 Fix incorrect IP Address associated with containers

* Make the container IP address configurable
* Make the container hostname configurable
* Add tests

Questions remaining:

* should we make `RuntimeUtils` work better? Allow IPv6?
* Should there be a admin-server IP / Host command line option? Right now you can set it via `application.yml` or environment variables:
  - `xd.container.hostname`
  - `xd.container.ip`

Jira: https://jira.spring.io/browse/XD-2239



As you can see that the place where the default values for container attributes are injected in `ContainerServerApplication` , the properties are resolved through **environment** only

```
private void setConfiguredContainerAttributes(ContainerAttributes containerAttributes) {
		Map<String, String> attributes = new HashMap<String, String>();
		for (PropertySource<?> propertySource : environment.getPropertySources()) {
```
Hence, these values are always available in the environment in `XdConfigLoggingInitializer` and that's the reason all the other values there use the similar approach.