Positioning toast

[nsantos16]

Description

We need to implement a position property on useToast hook, I think something like this

const { onOpen, onClose } = useToast(<CustomToast />, { position: 'bottom', positionOffset: 30 })

in which:

• position accepts (for now) bottom and top(default value) properties, which positioning the toast on center-bottom/center-top of the screen
• positionOffset accepts offset of the screen position, with a default value of 20