Version 1.51

(internals) Renamed FocusedWindow to NavWindow to match terminology of navigation branch

Merge 20a0fde Tidying up default clipboard handler for non Windows-OS (from Nav branch)

Merge 2545d75 from Nav - Tidying up, removed two unnecessary window flags from being exposed in imgui.h

Minor miscellaneous merges from Navigation branch to reduce divergence a little bit

ImRect::Clip() -> ClipWith() to clarify meaning, going to undo the change in Nav branch.

Removed tabs that slipped through the cracks

Columns: Caching columns clipping rectangles (#125)

Columns: Moved PushColumnClipRect() to imgui_internal.h

Columns: A set of column (and most importantly the right-most column) do not register its content to the parent, not affecting the window contents size. (#519, #125, #913)

Columns: Added ImGuiColumnsFlags_NoResize flag (internal). (#913, #125)

Columns: Moved BeginColumns/EndColumns/flags from #913 to imgui_internals.h + minor shallow tweaks. Removed demo code temporarily. (#125)

Merge branch 'master' of https://github.com/ggtucker/imgui into ggtucker-master ...

# Conflicts:
#	imgui.cpp
#	imgui.h

ImFontAtlas: Re-arranging code to simplify implementation of imgui_freetype. (#618)

ImFontAtlas: Re-arranging code to simplify implementation of imgui_freetype. (#618)

ImFontAtlas; Re-arranging code to simplify implementation of imgui_freetype (#618)

OpenPopupEx() internal tweaks to receive an ImGuiID, BeginPopupContextXXX shortening unnecessarily long identifier.

Undo part of 32dbe83 to keep the same name for both overloads (#891, #799)

TODO list update, comments

Renamed ImGuiSetCond_XXX type and enums to ImGuiCond_XXX, kept old enums under #ifdef IMGUI_DISABLE_OBSOLETE_FUNCTIONS

Added SetColorEditOptions(). ColorPicker4: context menu to select picker type and alpha bar. Reorganized flags (again!). (#346)

Internals: Added ImLineClosestPoint, ImTriangleClosestPoint helpers. Changing ImVec2 arg to const ImVec2&

Internals: Added ImDot(), ImRotate(), ImLerp(v2,v2,float) helpers.

Internals: Added ImTriangleBarycentricCoords() helper. Renamed ImIsPointInTriangle() to ImTriangleContainsPoint(), with different arg order.

Comments about parts of imgui_internal.h that will self-destruct.

ColorPicker4: hue/alpha bars draw arrows that would look right on all background. RenderArrow helper. (#346)

ColorEdit4: Picker spawned from ColorEdit4 has a preview for original/previous color with revert button - WIP not really happy with it being in ColorEdit4 code (#346)

ColorButton: Pretty much gave up with getting the checkerboard + AA + rounding + blending + offset all working together with every combination under the sun. It works as long as you don't sneeze. (#346)

RenderColorRectWithAlphaCheckerboard() in one layer to shunt out anti-alasing artefacts when rounded. Added ImLerp(int,int,float). (#346)

ColorButton, ColorPicker: painfully made RenderColorRectWithAlphaCheckerboard more friendly to using Rounding and Border in style, still not perfect :( (#346) + comments