Merge branch 'master' into docking

# Conflicts:
#	docs/CHANGELOG.txt
#	examples/imgui_impl_opengl3.cpp
#	imgui.cpp

examples/imgui_impl_sdl.h

@@ -17,6 +17,7 @@
 // https://github.com/ocornut/imgui
 
 #pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
 
 struct SDL_Window;
 typedef union SDL_Event SDL_Event;