Docs: add more links to the top of every examples and backends files.

examples/example_win32_directx12/main.cpp

@@ -1,6 +1,10 @@
 // Dear ImGui: standalone example application for DirectX 12
-// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
-// Read online: https://github.com/ocornut/imgui/tree/master/docs
+
+// Learn about Dear ImGui:
+// - FAQ                  https://dearimgui.com/faq
+// - Getting Started      https://dearimgui.com/getting-started
+// - Documentation        https://dearimgui.com/docs (same as your local docs/ folder).
+// - Introduction, links and more at the top of imgui.cpp
 
 // Important: to compile on 32-bit systems, the DirectX12 backend requires code to be compiled with '#define ImTextureID ImU64'.
 // This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.