Add Railway To README

[Lermatroid]

Pre-Requisites

• [x] Yes, I updated Authors.md OR this is not my first contribution
• [x] Yes, I included and/or modified tests to cover relavent code OR my change is non-technical
• [x] Yes, I wrote this code entirely myself OR I properly attributed these changes in Third Party Notices

Description of Changes

Adds Railway as a one-click deployment target. We have widely used it at my org, and its ease of deployment makes it a good hosting platform for time-constrained hackathons.

Related Issues

N/A