Speaker diarization with ASR ouputs
**Is your feature request related to a problem? Please describe.**

I am developing an API for a speaker diarization task with ASR (`/examples/speaker_tasks/diarization/offline_diarization_with_asr.py`). For my use case the script generates two useful outputs a `.json` that looks something like this:

```
{
	"status": "Success",
	"session_id": "example",
	"transcription": "thank you sunny day",
	"speaker_count": 4,
	"words": [
		{
			"word": "thank",
			"start_time": 0.0,
			"end_time": 0.6,
			"speaker_label": "speaker_1"
		},
		{
			"word": "you",
			"start_time": 0.7,
			"end_time": 1.1,
			"speaker_label": "speaker_1"
		},
		{
			"word": "sunny",
			"start_time": 1.5,
			"end_time": 2.1,
			"speaker_label": "speaker_2"
		},
		{
			"word": "day",
			"start_time": 2.2,
			"end_time": 2.3,
			"speaker_label": "speaker_2"
		}
	]
}
```

So we have the whole transcription which is very useful along with speaker labels for each of the spoken words. For API purposes this JSON is very handy however its contents are not very useful for practical applications. For diarization purposes and practical applications the script's `.txt` output is much more convenient:

```
[00:00.00 - 00:01.17] speaker_1: thank you
[00:01.54 - 00:02.33] speaker_2: sunny day
```

**Describe the solution you'd like**

Would it be possible to add the information from the `.txt` output to the JSON? E.g., something like:

```
	"diraization": [
		{
			"transcription": "thank you",
			"start_time": 0.0,
			"end_time": 1.17,
			"speaker_label": "speaker_1"
		},
		{
			"transcription": "sunny day",
			"start_time": 1.54,
			"end_time": 2.33,
			"speaker_label": "speaker_2"
		}
	]
```

**Describe alternatives you've considered**

I took a look at the code and I believe I would could code this myself, would you be interested in a pull request that modifies the output JSON?
