Updated Ogre bindings (#2619) ...

And support python

Internals: Columns: Poke into WorkRect and use them in the GetContentRegionMax() functions. This should be a no-op, but preparing us to transition toward using WorkRect instead of ContentRegionRect. ...

Removed one use of ContentsRegionRect.

Disable -Wpragmas warning in GCC to avoid relying on version checks, as unusual/forks/mods don't appear to always have same warning<>version. (#2618) ...

+ Fix version number in imgui.h

ImDrawList: Fixed CloneOutput() helper crashing. Also removed unnecessary risk from ImDrawList::Clear(), draw lists are being clear before use each frame anyway. (#1860)

ImDrawList::ChannelsSplit(), ImDrawListSlitter: Fixed an issue with merging draw commands between channels 0 and 1. (#2624) Introduced by cef88f6.

Removed redirecting functions/enums that were obsoleted in version 1.51 (June 2017): ImGuiCol_Column*, ImGuiSetCond_*, IsItemHoveredRect(), IsPosHoveringAnyWindow(), IsMouseHoveringAnyWindow(), IsMouseHoveringWindow(), IMGUI_ONCE_UPON_A_FRAME.

Version 1.72 WIP

Version 1.71 + comments

Internals: Reworked RenderTextEllipsis() to satisfy what we need for table headers.

Readme, comments, dear imgui prefixes

CollapsingHeader: Minor fix to align right side of frames (which is extruded past the Work/Contents rect) with clipping rectangle.

Log/Capture: Fixed BeginTabItem() label not being included in a text log/capture. ...

Extracted tab rendering code into a RenderTextEllipsis() function.

ImDrawListSplitter: Don't merge draw commands when crossing a VtxOffset boundary + Renamed fields ImDrawChannels to consistently suggest those are internal structures.

ImDrawListSplitter: Fix idx offset when merging (cef88f6) (#2591)

Window: child windows outer decorations (e.g. scrollbar) are rendered as part of their parent window, avoiding the creation of an extraneous draw command. ...

+ Metrics: inverted color of clip rect vs vertices bounding box when hovering a draw command, so the color matches the per-vertex preview.

Internals: Added drawlist and color arg to RenderArrow(), RenderBullet(). Reordered args for RenderPixelEllipsis.

imgui-test: Added IMGUI_TEST_ENGINE_LOG macro to emit into test log from core or user land.

Made PushID() behave the same in 32-bit and 64-bit, by not padding the integer into a void*. (Also technically faster.)

Synced/merged minor cruft from docking branch to minimize drift. AFAIK the only meaningful no-op change is that the call UpdateHoveredWindowAndCaptureFlags() was moved above UpdateMouseMovingNewFrame() to match what docking branch has been doing for a while.

ImDrawCallback: Allow to override the signature of ImDrawCallback by #define-ing it. This is meant to facilitate custom rendering back-ends passing local render-specific data to the draw callback.

Revert "Changed syntax for (very rarely used) IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT mechanism, instead you only need to '#define ImDrawVert MyDrawVert' to use this feature, avoiding the need to declare the entire structure within an awkward macro. Using the old macro will now error with a message pointing you to the new method. (#38, #103, #1172, #1231, #2489)" ...

This reverts commit 597c024.

Changed syntax for (very rarely used) IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT mechanism, instead you only need to '#define ImDrawVert MyDrawVert' to use this feature, avoiding the need to declare the entire structure within an awkward macro. Using the old macro will now error with a message pointing you to the new method. (#38, #103, #1172, #1231, #2489)

Window: Fixed one case where auto-resize by double-clicking the resize grip would make either scrollbar appear for a single frame after the resize. Moved Scrollbar visibility block.

Internals: Moved scrollbar visibility calculation block below the call to UpdateManualResize(). This commit is _intended_ to have no side-effect (next commit will). Also moved ItemWidthDefault calculation below rectangles.

Scrollbar overlap an extra WindowBorderSize amount on the left to make all distances consistent. Reverted to BorderSize not affecting work/contents rectangles. Scrollbar, Style: Changed default style.ScrollbarSize from 16 to 14.

Internals: Minor no-op tidying up toward solving the WindowPadding / WindowBorderSize / ScrollbarSize overlapping mess. ...

+ Demo: Use SetScrollY().

Fixed newly created window (e.g. appearing child window) from having scrollbar active on the first frame. (fix 6e03b27) + reworded code a little. (+1 squashed commits) ...

Fixed auto-resize with AlwaysVerticalScrollbar or AlwaysHorizontalScrollbar flags not taking account of the expect scrollbar sizes.

Internals: Storing ScrollMax into a member. Mostly to facilitate debugging. Also locking down window->Scroll slightly lower in the Begin function.

TextWrapped, PushTextWrapPos(0.0f) within a window with horizontal scrolling from not covering the full horizontal area (previously only worked with an explicit contents size).

Internals: Renamed SizeContents to ContentSize, SizeContentsExplicit to ContentSizeExplicit. Tweaked Metrics->Show Rectangles functionality.