Add support for getting additional pricing details

[TomSeldon]

Aside from the event price (already available), there are additional prices for things such as:

Car:

• Extra driver
• Passenger
• Helmet hire
• Tuition
• Garage hire

Bike:

• Tyre warmers
• Tuition

These details are not available from the event list page, and instead the detail page needs to be scraped. This is costly to do when getting all events (as each one would require another request). The number of requests would go from 1, to n+1 (where n is the number of events).

Possibilities:

Add getEventDetails (eventId: number, vehicleType: VehicleType) method for getting further details for an event. This is complicated further by needing to know whether it's a car or bike event. The detail URLs for each vehicle type are different, yet both work. For example:

• https://www.trackdays.co.uk/book/cartrackday/10978/
• https://www.trackdays.co.uk/book/biketrackday/10978/

The same event is accessible by both car and bike URLs, though information (such as above pricing details) are omitted if the wrong URL is used.

I'm not sure what else is available on the detail view that is not available on the event list, so perhaps getAdditionalPrices would be a better method name.

Edit: Additional information that would of use would be the event description.