Add Vulkan Timestamp Queries and Plots

[CaffeineViking]

We'll probably want to profile the performance gains (most likely losses) of the SPIR-V conversion, and also have some way to easily profile the app. Of course, we could use RGP to do this, but it would be better to have a way to do this "live". I propose we gather query results for timestamps for each stage of our render, i.e. shadow map rendering pass, depth map rendering pass, each compute dispatch of the OIT solution, the mesh drawing, and (optionally, if our LoD technique uses raster too for strands), raster hair rendering time. We could also be extra fancy and add ImGui plots for the timings, a bit like in the SEED's Vulkan PICA PICA.

[CaffeineViking]

Implementation complete, it's now really easy to profile in-between locations within a command buffer. The output is automatically reflected in IMGUI as a plot of the per-frame timings and an average over a second.