Adding textures capabilities

* Added Texures to the two sample cubes
* Modified mesh structure
	- mesh now contains indices and vertices
	- Vertices contain vertices and uv's (later on they will also
	contain normals)

Solution definitely not perfect and needs improvement.

BarinkEngine/premake5.lua

@@ -16,7 +16,7 @@ project "BarinkEngine"
     "../libs/assimp/include",
     "../libs/glad/include",
     "../libs/glfw/include",
-    "../libs/tinygltf",
+   -- "../libs/tinygltf",
     "../libs/glew/include",
     "../libs/glm",
     "../libs/ImGui",