Added Features
- [x] Created BaseWebsocket class
- [x] Created OrderEventsWS class to interact with the order events websocket
- [x] Created MarketDataWS class to interact with the market data websocket
- [x] Added greater support for heartbeat API's
- [x] Improved the Cached metaclass
- [x] Added support for sandbox urls
TODO
- Add filter options to order events websocket
- Improve options to add and remove orders from market data websocket
- Add options to choose whether a particular class is cached or not
- Export recorded data from market data or order events websocket into a matplotlib graph
- Export recorded data from market data or order events websocket into a sqlite, postgresl or sql database
- Add test for the cached metaclass