Added skeleton values and warning

Don't put real values in this file!
Added format to Sale. Denormalization for the win

The point is so that we don't have to join the Sales table to the Albums
table to discover the format.
Added support for Google Pie Charts

Also made the generators more generic by removing DateTime and
BigDecimal type parameters
Added ability to group by format

Also some minor refactoring to support more generic output generators
Added format to test sale data
Added Sales by Format pie chart
Show a legend for pie charts
Added class for Shopify Product
Added ability to create a new product
Create new product