Maintain historical records to measure compliance / improvements over time.

[obrien-j]

Just throwing this in as a place holder, specifically within tracker/data/cli.py def run,
we're currently nuking the entire dataset at runtime which while great for freshness, is stealing away some valuable historical data.

Suggest we take a look at the backend and see how we could at least set aside previous scan results/reports/etc, even if there is no clean way to present the data currently.

#totallynotworking

[ptd-tbs]

Currently, we are storing the scan results as separate files in a storage account. Ideally, we need to store the results of the scans in the database so we can more easily extract the data. Specifically, to start, appending the results of the percentage of sites enforcing HTTPS would help to provide a basic baseline to track progress over time.

[sayaHub]

In order to preserve the report result of each scanner run, I will also save that report under a new collection called "historical" in the database so that we can easily query against it. For now, we feel that is not necessary to also keep the past result of each domain scan in the database, if we ever have the need to see past result, we can retrieve it in the Azure Storage Account.