Enhance timing panel to give more granular results

[danielcompton]

Correct timing skew from subscriptions running while views render

• re-frame's traces measure elapsed time between the start and end of the tracing period. This measures the total elapsed time. If a subscription runs while a view is rendering, the time the subscription took to run is measured in the subscription's trace, as well as the parent view.

In the traces and timing panels we need to calculate the 'self' time for each trace and use that when calculating the time taken to run views and subscriptions.

More granular results

• Once we do this we can separate out the timing for each animation frame into view, subscription, and React etc.

Collect event and effect timing

• We don't have granular enough traces around handling an event, we need to add more tracing here.