Add Linux support

- Add linux build system using MakeGen
- Fix a swapchain validation error, likelydue to my linux system using a
  different vulkan version
- Make DescriptorPool take in amount of descriptors it needs, instead of
  allocating a mass amount for every pool, causing loads of RAM/VRAM usage

CopiumEngine/src/copium/core/Window.h

@@ -51,4 +51,4 @@ namespace Copium
     static void WindowFocusCallback(GLFWwindow* window, int focused);
     static void MouseScrollCallback(GLFWwindow* window, double xoffset, double yoffset);
   };
-}
+}