Add form for new internship partial (modal)
Add new action
a slot needs to be known in order to create an internship
the build method somehow creates a connection between slot and internship
add new_internship_path to modal link

we are also sending along the slot_id from the show view with new_internship_path(:slot_id => slot.id). we go to the new action where we in turn find the slot by the passed on slot_id and with that build an internship...which we then use in the form...
I am still confused...