Internals architecture revamping

[jpbruyere]

Global architecture besides following cairo api was modeled with vulkan's one in mind:

• Pipeline based rendering
• Vulkan commands and descriptors threading model

With several new ideas in mind, I need to add some modularity into internals, the goal is to be able to test:

• Vulkan Shader object #146
• Dynamic rendering #147
• Compute, Mesh or DGC based stroking and tessellation. #148
• Also a cpu only fallback mode with maybe pixman #149
• Vulkan Profiles #150
• Variable shading rate in a single run command #151
• Precise gpu and cpu Timing measures, maybe integrate tracy profiler. #152