Add enableTracing Option

[smeubank]

A new simplified options for configuring to turn tracing & performance on should be added to all SDKs. For each SDK the default sample rate should be agreed upon.

Docs do not need to be updated yet, nor the onboarding wizard. This can wait until the top level options are added to a number of SDKs and we decide if we want to configure the default onboarding experience, for all new users.

See develop docs for more information. This is a non-breaking change to be clear. Any of the three options should enable performance, alone or in combination

Open point:

recommend default it 1.0 or 100%. Can discuss if it should be less.