add hand cursor support (+11 squashed commit)

Internals: Settings: Simple optimization caching index into the settings buffer, to remove an unnecessary O(N*M) search during saving. (with N=active root windows during the session, M=stored settings which grows over time)

ImVector: Added index_from_pointer() helper.

Allow menu windows from ignoring the style.WindowMinSize values so short menus are not padded. (#1909)

Double-click on resize grip doesn't need to test HoveredWindow (as button has the flattenchild flag anyway) + double-click on title bar verify that we don't have overlapping items to allow contents in title bar. + Comments

Examples: Apple: Fixed paths of GLFW+GL2 example. (#1906) Update ignore list.

Internals: Various renaming. e.g. NewFrameUpdateHoveredWindowAndCaptureFlags() to UpdateHoveredWindowAndCaptureFlags() + exposed UpdateMovingWindow() in imgui_internal.h.

ArrowButton: Fixed to honor PushButtonRepeat() setting (and internals' ImGuiItemFlags_ButtonRepeat). Setup current line text baseline so that ArrowButton() + SameLine() + Text() are aligned properly.

Internals: Moved some of the SliderBehaviorT code into SliderBehavior to reduce the amount of instanciated code.

Examples: OpenGL3: Remove misleading or unnecessary "#version 150" strings.

Version 1.63 WIP

Demo: Fixed incorrect response to Begin() returning false in overlay demo (which cannot happen since we don't have a title bar, but that doesn't make it a good behaving demo!).

Examples: Fixes.

Demo: Fixed mismatched TreePush/TreePop in Property Editor, due to incorrect revert in 826d771 (#1895)

Examples: Vulkan: nverted the parameters to ImGui_ImplVulkan_RenderDrawData() to be consistent with other bindings.

Version 1.62

Examples: DirectX12: Moved the ID3D12GraphicsCommandList* parameter from ImGui_ImplDX12_NewFrame() to ImGui_ImplDX12_RenderDrawData() which makes a lots more sense. (#301)

Examples: The functions in imgui_impl_xxx.cpp are prefixed with IMGUI_IMPL_API (which defaults to IMGUI_API) to facilitate some uses. (#1888) + Comments in imgui.h

Examples: SDL+OpenGL2: Fixed Makefile. (#1886)

Examples: Fixed bindings to use ImGuiMouseCursor_COUNT instead of old name ImGuiMouseCursor_Count_ so they can compile with IMGUI_DISABLE_OBSOLETE_FUNCTIONS. (#1887)

Readme, Links, Bindings

Fixed warnings + readme

Examples: OSX: Added clipboard support. Fixed ignore list for xcode cruft. Comments about broken keys. (#1873)

Added assert in TreePop() to ease catching ID stack underflow earlier.

Revert 640c0566: TreeNode: Fixed nodes with ImGuiTreeNodeFlags_Leaf flag always returning true which was meaningless -> more flexible to keep allowing it by default so it setup an ID scope.

Added _None values to various enum flags, useful for readability and some coding style likes it. (Unfortunately we can't refer to them as default value in imgui.h functions because they need to be declared below).

Speculative fix for Win32 clipboard handler if SetClipboardText() fails + Minor fix for static analyzer + using :: prefix when calling in Win32 functions.

Examples: Allegro5: Added support for ImGuiConfigFlags_NoMouseCursorChange flag. Added clipboard support. Unindexing buffers ourselves as Allegro indexed drawing primitives are buggy in the DirectX9 back-end.

Comments + missing changelog bits in 1.52 for SetNextWindowPos, SetNextWindowPosCenter. (obsolete #771)

Added IsItemDeactivatedAfterChange() if the last item was active previously, isn't anymore, and during its active state modified a value. Note that you may still get false positive. (#820, #956, #1875)