Streamline and package "data update" step

[geneorama]

Right now this process assumes a manually created single point in time download.

We need a way to refresh / add new data. This should be accomplished by adding function(s) that encompass the entire data step.

It makes sense to tackle some other issues in this step:

• Fix Weather import process (issue 32)
• Convert latitude to numeric during import (issue 31)
• Add "Cleaned" facility type to data (issue 30)
• Merge logic (issue 22) This issue is almost a repeat of the current issue (38)
• Remove old data files and put into top level DATA folder (new issue)

[geneorama]

Specifics of Merge step:
Primary data source:: Food inspections
Merged sources:

• Food inspection history
• Associated business characteristics
• Weather data
• Heat data variables

[geneorama]

@tomschenkjr Also updated the README.md, please review