Better deep merge to handle arrays

Changed

• mergeContextData in TrackingProvider uses deep merge to merge payload and options context values.
• trigger function in TrackingProvider uses deep merge to merge context data with trigger data.

Structured Data Support

• Added new payload and eventPayload properties which accept any formatted data object. fields and eventFields are marked deprecated and will only be used if payload / eventPayload not specified.
• Update the options object so the values can be any rather than just strings.