Enhanced subtitle generation with CLI options

I'm impressed by the quality of generated subtitle in English. I would like see enhanced functionality by having CLI option to have more control on the generated subtitle.

## Suggested parameters

- Word by line (currently fixed at 7)
- Silence time before creating another line
- Line per screen (currently only one)

## Issue
When working on auto generated subtitle I see many sentences ends at non optimal position so I would like to increase "word by line" and "silence to new line" easily so I can later slice them according to my need instead of going back and forth manually between lines to get just one word to the previous one or the later one.

## Example

Vosk generated:

```
11
00:00:50,970 --> 00:00:54,270
millions of Americans motorcycles represent freedom rugged

12
00:00:54,270 --> 00:00:57,120
individualism the pleasures of roaring along the

13
00:00:57,120 --> 00:01:00,390
open road while the wind streams streams

14
00:01:00,390 --> 00:01:01,200
through your hair
```
Apparently I have to move few words between lines and fix timing.

Would become if I can modify the `vosk-transcriber` parameters:

```
11
00:00:50,707 -->00:00:57,659
for millions of Americans motorcycles represent freedom rugged individualism the pleasures of roaring along the open road

12
00:00:57,660 --> 00:01:01,200
while the wind streams streams through your hair
```

Then I can easily slice them at the points I want using tools like `subtitld` which allows me to select a position in subtitle and slice lines.