Examples: SDL+DX11: Changelog, readme, batch files, fixed vcxproj, minor stylistic fixes + minor sync of other main.cpp files. (#2632)

examples/example_glfw_vulkan/main.cpp

@@ -440,6 +440,7 @@ int main(int, char**)
         ImGui_ImplVulkan_DestroyFontUploadObjects();
     }
 
+    // Our state
     bool show_demo_window = true;
     bool show_another_window = false;
     ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);