- refactored scene_main to be able to share code between software and
  hardware renderers, while still sharing code between terminal software
  renderer and graphical software renderer
- made the hardware renderer use scene objects vertices and transforms,
  instead of hardcoded ones
- made the hardware renderer use the scene's camera
- made .obj parser create Vector3 instead of Vector4, which didn't made
  sense
- removed unnecessary std::
- lots of small changes

map values[i * 4 + j] to values[i + j * 4], meaning that values[1] is
now the second line, first column, instead of first line, second column

- fixed aspect ratio being the inverse of what it's supposed to be
- use std::chrono::high_resolution_clock instead of system_clock
- convert ellapsed time to float representing seconds
- renamed engine::math::Matrix4::projection to perspective
- use [0,1] instead of [-1,1] for the range of z values, to be aligned
  with vulkan
- added engine::math::Matrix4::{look_at,transpose}

- made every swapchain image have it's own render finished semaphore
- renamed draw fence to in-flight fence (fence_draw to fences_in_flight)
- made present complete semaphores and in-flight fences "per in-flight
  frames", meaning that if we have at most 2 in-flight frames, we use 2
  present complete semaphores and 2 in-flight fences
- recreate swapchain when needed
- more refactoring
- added fps counter