Taskwarrior hook script doesn't start recording new active task

When running the following:
```
task add start:now Do the thing
```
one expects that this a) creates the task and b) starts the recording.
But instead it just creates the task and doesn't start the recording.

This is due to the hook script only being called when a task is modified but not when a task is created. Related: GothenburgBitFactory/task-timewarrior-hook#17.

Please be aware that the following is also possible and in my personal workflow quite common:
```
task add start:-30min Do the thing
```

Thanks for your continuing effort to deliver great cli-based to do manager.