Cannot change field types via schema file / Ratel

Hi, I tested on version 1.1.1

I added a schema like this:

type A {
    a
}
type B {
    b
}
type C {
    c
}
a: string .
b: uid .
c: [uid] .

I can see it in ratel as:
image
Which is what I would expect.
This field below is ignored currently:

Look at this post regarding constrains: Is it possible to impose restrictions on variables in Dgraph? - #3 by martinmr