Merge branch 'master' into docking

# Conflicts:
#	backends/imgui_impl_glfw.cpp
#	backends/imgui_impl_osx.mm
#	backends/imgui_impl_sdl.cpp
#	backends/imgui_impl_win32.cpp
#	imgui.cpp
#	imgui.h
#	imgui_internal.h
#	imgui_widgets.cpp

examples/example_win32_directx11/main.cpp

@@ -284,5 +284,5 @@ LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
         }
         break;
     }
-    return ::DefWindowProc(hWnd, msg, wParam, lParam);
+    return ::DefWindowProcW(hWnd, msg, wParam, lParam);
 }