Initial model prediction runtime with support for presigned model get and output post URLS

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Numerai Model Prediction Docker Environment

Presigned GET and POST urls are used to ensure that only the specified model is downloaded during execution
and that model prediction uploads from other models are not accessed or tampered with.

Presigned S3 model URL

The --model arg is designed to accept a pre-signed S3 GET URL generated via boto3

params = dict(Bucket='numerai-user-models', Key='integration_test')
presigned_model_url = s3_client.generate_presigned_url("get_object", params, ExpiresIn=600)

Presigned S3 post URL

The --post_url and --post_data args are designed to accept a pre-signed S3 POST URL + urlencoded data dictionary
generated via boto3

presigned_post = s3_client.generate_presigned_post(Bucket='numerai-user-models', Key='integration_test', ExpiresIn=600)
post_url = presigned_post['url']
post_data = urllib.parse.urlencode(presigned_post['fields'])