Removes unused files

[maxneuvians]

Fixes: Removes un-used files that we inherited from the fork.

These include:

• FORK.md - a collection of changes compared to upstream. At this point the code base is so divergent that it does not make sense to keep it
• deploy/kubernetes/* - kubernetes manifest files used to deploy the server to a kubernetes cluster. We use the AWS ECS
• dev.yml and railgun.yml - part of Shopify dev tooling
• scripts/create-seed-data - seeding script we do not use
• scripts/create-upload-payload-for-load-testing - load testing script we do not use

Also fixes CI to Go 1.14

Description of what your PR accomplishes:

Declutter the code.

Anything the reviewers should focus on? Any discussion points?

Do we actually need any of the files.