Changelog, minor tweaks. (#2585)

Added full "Dear ImGui" prefix to the title of "Dear ImGui Demo" and "Dear ImGui Metrics" windows. Shortened amount of nodes in columns>tree demo.

Comments, todo entries, moved ImGuiSelectableFlagsPrivate in higher ranges to match others.

ColorEdit: Fixed the color picker popup only displaying inputs as HSV instead of showing multiple options. (#2587, broken in 1.69 by #2384).

Style: Added style.WindowMenuButtonPosition (left/right, defaults to ImGuiDir_Left) to move the collapsing/docking button to the other side of the title bar.

Internal: CloseButton takes an upper-left corner + a size to be consistent with similar widgets.

Fixed InputScalar, InputScalarN, SliderScalarN, DragScalarN with non-visible label from inserting style.ItemInnerSpacing.x worth of trailing spacing.

ImFontGlyphRangesBuilder: Fixed unnecessarily over-sized buffer, which incidentally was also not fully cleared. Fixed edge case overflow when adding character 0xFFFF. (#2568)

Fixed crash when appending with BeginMainMenuBar() more than once and no other window are showing. (#2567) + comments

Update changelog, comments, made empty/no-text clipboard return NULL as with other implementation. Minor style tweaks. (#2546) ...

Fixed IMGUI_DISABLE_WIN32_FUNCTIONS not disabling IME code.

Fixed uses of IsItemDeactivated(), IsItemDeactivatedAfterEdit() on multi-components widgets and after EndGroup(). (#2550, #1875)

Fixed InputFloatX, SliderFloatX, DragFloatX functions erroneously reporting IsItemEdited() multiple times when the text input doesn't match the formatted output value (e.g. input "1" shows "1.000"). It wasn't much of a problem because we typically use the return value instead of IsItemEdited() here. (#1875, #2034)

Internal: Renamed fields + minor tweaks (probably shallow break stack-layout pr, sorry!)

Renamed SetNextTreeNodeOpen() to SetNextItemOpen(). Refactored SetNextItemXXX stuff to match SetNextWindowXXX code closely.

FreeType: Added RasterizerFlags::Monochrome flag to disable font anti-aliasing. (#2545) Combine with RasterizerFlags::MonoHinting for best results.

IO: changed AddInputCharacter(unsigned short c) signature to AddInputCharacter(unsigned int c). ...

Examples/Backends: Don't filter characters under 0x10000 before calling io.AddInputCharacter(), the filtering is done in io.AddInputCharacter() itself. This is in prevision for fuller Unicode support. (#2538, #2541)

Internal: Scrollbar: Further sane simplification (using InnerMainRect instead of duplicating calculations).

Separator: Revert 1.70 "Declare its thickness (1.0f) to the layout" change (c5d83d8a). It's not incorrect but it breaks existing some layout patterns. Will return back to it when we expose Separator flags.

Internal: Refactored Separator into SeparatorEx(), exposed ImGuiSeparatorFlags_SpanAllColumns in imgui_internal.h and support without. (#759) + misc comments

Columns: Fixed Separator from creating an extraneous draw command. Fixed Selectable with SpanAllColumns flag from creating an extraneous draw command. (#125)

Version 1.71 WIP + fixed minor typo

Version 1.70

Examples Readme and Changelog tweaks, added #2527, re-ordered examples/README alphabetically.

Window: Fixed SetNextWindowSizeConstraints() with non-rounded positions making windows drift. (#2067, #2530)

Misc: Made IMGUI_CHECKVERSION() macro also check for matching size of ImDrawIdx.

Selectable: With ImGuiSelectableFlags_AllowDoubleClick doesn't return true on the mouse button releas efollowing the double-click. Only first mouse release + second mouse down (double-click) returns true. Likewise for internal ButtonBehavior() with both _PressedOnClickRelease | _PressedOnDoubleClick. (#2503)

Demo: Improved trees in columns demo. (#2136)

ImDrawCallback_ResetRenderState: Added Metal.

ImDrawCallback_ResetRenderState, Examples: Added support for reset render state callback. (#2037, #1639, #2452)

Obsoleted GetContentRegionAvailWidth(), use GetContentRegionAvail().x instead. Kept inline redirection function.