add a flag similar to skip_n_tasks but more intuitive

[FrancoisPgm]

I was thinking it might be easy to have an argument that would replace skip_n_tasks for video segments, the difference being you tell which segment you want to start with rather than the number of segments to skip.

For example for friends-s6 instead to putting --skip_n_tasks 12 you would put --start_with s06e07a.

It's not that big of a deal but if it is quick to implement, that would enhance the API at minimal cost.

[bpinsard]

I think it would be even better to have a savestate as for mario.