staircase model and visualisation code (post black formatting)

[cmbrennan002]

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Description

This PR does two things (probably should have been separate branches - sorry - but hopefully not too big).

1. Trains a staircase only model Add relevant config files Add code to prodigy_to_yolo to relabel a staircase only set (STAIRCASE = 0)

2. Adds code to visualise an image with labels in a notebook/ from the terminal Edit getters to also download jpg files Add relevant functions to utils

Fixes # (issue)

11 - staircase only model

Instructions for Reviewer

• The staircase model and labels are saved in s3, alongside equivalent window/room/door
• The visualisation code is really meant as a working tool, but you can test it by running the file and it will display three images.