Nested (decorated?) jobs

Hey,

I wanted to have a job that runs another job. For instance, have a job sending out emails and that is it's only concern. Then have a job that does logging of the job that is has been provided to run.

The logging job

```
internal class LogSmsJob
{
private readonly IBackgroundJobClient _backgroundJobClient;

public LogSmsJob(IBackgroundJobClient backgroundJobClient)
{
_backgroundJobClient = backgroundJobClient;
}

public string EnqueueLog(Expression methodCall)
{
Debug.WriteLine("log before");

var jobId = _backgroundJobClient.Enqueue(methodCall);

Debug.WriteLine("log after");

return jobId;
}
}
```

Queueing of the sms job through the LogSmsJob

```
var smsJob = new SmsNotificationJob(); // TODO: provide config to constructor
var logJob = new LogSmsJob(_backgroundJobClient);
// enqueue with Hangfire
_backgroundJobClient.Enqueue(
() => logJob.EnqueueLog(() => smsJob.Send(_smsConfig, toPhoneNumber, text, null)));
```

It produces the following exception

`System.NotSupportedException: 'Anonymous functions, delegates and lambda expressions aren't supported in job method parameters: it's very hard to serialize them and all their scope in general.'`

Is there some way we can have nested (decorated, ie decorator pattern style) jobs with Hangfire?

Obviously the easy solution would be to bring the logging into the actual working job itself but I'd rather keep jobs SRPed if you know what I mean.

Start with the LogSmsJob.EnqueueLog and IBackgroundJobClient.Enqueue calls shown in the issue, then trace how Hangfire validates and serializes job method parameters. Determine the supported scope for nested or decorator-style jobs and define done as either a documented supported approach with coverage or a clearly documented limitation.

Written by the indexing model from the issue text.