[Feature] Add Primary Dealer Positioning To Economy

[deeleeramone]

1. Why?:

   • Adding open source data to the Platform.

2. What?:

   • This data is a subset of Primary Dealer Statistics, a series published weekly by the New York Federal Reserve.
   • Values are net position (long - short) and are in millions of $USD.
   • Select the asset type with the 'category' parameter with defined choices.

3. Impact:

   • More stuff to maintain.

4. Testing Done:

   • Unit/integration tests.
   • CLI