Squashed 'external/imgui/imgui/' content from commit d4ddc46e7

git-subtree-dir: external/imgui/imgui
git-subtree-split: d4ddc46e7773e9a9b68f965d007968f35ca4e09a

.gitignore

@@ -0,0 +1,60 @@
+## OSX artifacts
+.DS_Store
+
+## Dear ImGui artifacts
+imgui.ini
+
+## General build artifacts
+*.o
+*.obj
+*.exe
+examples/build/*
+examples/*/Debug/*
+examples/*/Release/*
+examples/*/x64/*
+
+## Visual Studio artifacts
+.vs
+ipch
+*.opensdf
+*.log
+*.pdb
+*.ilk
+*.user
+*.sdf
+*.suo
+*.VC.db
+*.VC.VC.opendb
+
+## Getting files created in JSON/Schemas/Catalog/ from a VS2022 update
+JSON/
+
+## Commonly used CMake directories
+/build*/
+
+## Xcode artifacts
+project.xcworkspace
+xcuserdata
+
+## Emscripten artifacts
+examples/*.o.tmp
+examples/*.out.js
+examples/*.out.wasm
+examples/example_glfw_opengl3/web/*
+examples/example_sdl2_opengl3/web/*
+examples/example_emscripten_wgpu/web/*
+
+## JetBrains IDE artifacts
+.idea
+cmake-build-*
+
+## Unix executables from our example Makefiles
+examples/example_glfw_metal/example_glfw_metal
+examples/example_glfw_opengl2/example_glfw_opengl2
+examples/example_glfw_opengl3/example_glfw_opengl3
+examples/example_glut_opengl2/example_glut_opengl2
+examples/example_null/example_null
+examples/example_sdl2_metal/example_sdl2_metal
+examples/example_sdl2_opengl2/example_sdl2_opengl2
+examples/example_sdl2_opengl3/example_sdl2_opengl3
+examples/example_sdl2_sdlrenderer/example_sdl2_sdlrenderer