Added current model indicator with an * when --listmodels is called

[mchoccie]

What this Pull Request (PR) does

Trying to add a small and simple feature for my first contribution. Whenever 'fabric --listmodels' is called, the output will denote the currently used model with an asterisk after it. Hopefully this will give users a better idea of the current model they've set Fabric to utilize.

Related issues

closes #446

Screenshots

[auryn31]

Just encountered the same thing and would love having it in. Would maybe write a model print helper function, to not have so many if repetitions and only one place to change the pattern of what is the current model and what not maybe would also have instead of a * something like (current)

[mchoccie]

Hey @auryn31 , I implemented the changes you mentioned. What do you think?

[danielmiessler]

This is great, but we're moving to Go. Please resubmit if this isn't fixed after the migration. Thank you!