Feat/modal migrate to typescript

[M-i-k-e-l]

Migrate Modal (and dependency) to typescript

[ethanshar]

Consider changing to typeof Modal it will automatically pass the type of Modal class with all of its static member.
This is what we do in our Button component, let's see if it works here as well.

[M-i-k-e-l]

Done

[M-i-k-e-l]

I've just now noticed that we send cancelIcon={null} in our ModalScreen to remove the default icon, but null is not actually allowed, should I simply add null as an option with an explanation or do you want to think on a better solution?