Make QueryType a regular Vulkan enum

[Rua]

Changelog:

### Breaking changes
Changes to queries:
- `QueryType` is now a regular Vulkan enum like others in Vulkano.
- The `QueryType::result_len` method is moved to `QueryPool`, and now takes result flags into account.
- `QueryPoolCreateInfo` now has a `pipeline_statistics` field to specify the pipeline statistics flags.
- The `CommandBufferInheritanceInfo::query_statistic_flags` field is renamed to `pipeline_statistics` to match Vulkan.

This brings Vulkano a bit closer to Vulkan again.