Create training materials page

[chopchop505]

We have training materials that should be accessible to signed in users. We want to keep the training materials private. I think an easy solution would to store them all in a private s3 bucket, where we can access them via presigned urls.

On the server, create a few routes

GET /api/training
This method queries the bucket, and returns a list of all training materials

GET /api/training/:id
This method generates a presigned url (https://docs.aws.amazon.com/AmazonS3/latest/dev/ShareObjectPreSignedURL.html) that allows the user to download the materials

On the client, create a new page (/training)
The page should list all training materials, and a download button

[chopchop505]

@garnertb Do you have any issue posting training materials?