Pass names, scopes, and timings

[kvark]

This helps us annotate the command scopes, capture the timers, and put GPU crash markers.
PR also adds the timing support.

Fixes #170
Closes #174
Depends on:

• Add ComputePassDescriptorRef::set_dispatch_type gfx-rs/metal-rs#335

• Add CounterSampleBuffer::resolve_counter_range gfx-rs/metal-rs#336

• Add AccelerationStructurePassDescriptor gfx-rs/metal-rs#337

• API

  • every pass now gets a name. And there is a flag at context creation... That's it. That's all of the API.

• Vulkan

  • 

• Metal

  • 

• GLES

  • 

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Particle example:

[kvark]

Proceeding with using https://github.com/kvark/metal-rs/tree/blade