Merge branch 'master' into docking

# Conflicts:
#	backends/imgui_impl_dx10.cpp
#	backends/imgui_impl_dx10.h
#	backends/imgui_impl_vulkan.h
#	backends/imgui_impl_win32.cpp
#	docs/CHANGELOG.txt
#	examples/README.txt
#	examples/example_glfw_opengl2/main.cpp
#	examples/example_glfw_opengl3/main.cpp
#	examples/example_glfw_vulkan/main.cpp
#	examples/example_sdl_directx11/main.cpp
#	examples/example_sdl_opengl2/main.cpp
#	examples/example_sdl_opengl3/main.cpp
#	examples/example_sdl_vulkan/main.cpp
#	examples/example_win32_directx10/main.cpp
#	examples/example_win32_directx11/main.cpp
#	examples/example_win32_directx12/main.cpp
#	examples/example_win32_directx9/main.cpp
#	imgui.cpp
#	imgui.h
#	imgui_demo.cpp
#	imgui_internal.h

examples/example_glut_opengl2/main.cpp

@@ -1,5 +1,6 @@
-// dear imgui: standalone example application for GLUT/FreeGLUT + OpenGL2, using legacy fixed pipeline
-// If you are new to dear imgui, see examples/README.txt and documentation at the top of imgui.cpp.
+// Dear ImGui: standalone example application for GLUT/FreeGLUT + OpenGL2, using legacy fixed pipeline
+// 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
 
 // !!! GLUT/FreeGLUT IS OBSOLETE SOFTWARE. Using GLUT is not recommended unless you really miss the 90's. !!!
 // !!! If someone or something is teaching you GLUT in 2020, you are being abused. Please show some resistance. !!!
@@ -116,7 +117,7 @@ int main(int argc, char** argv)
     ImGui::StyleColorsDark();
     //ImGui::StyleColorsClassic();
 
-    // Setup Platform/Renderer bindings
+    // Setup Platform/Renderer backends
     ImGui_ImplGLUT_Init();
     ImGui_ImplGLUT_InstallFuncs();
     ImGui_ImplOpenGL2_Init();