Version 1.71 WIP + fixed minor typo

Version 1.70

Merge branch 'master' into docking ...

# Conflicts:
#	examples/README.txt
#	examples/imgui_impl_dx9.cpp
#	imgui.cpp
#	imgui.h

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

Merge branch 'master' into docking ...

# Conflicts:
#	examples/imgui_impl_dx10.cpp
#	examples/imgui_impl_dx11.cpp
#	examples/imgui_impl_dx12.cpp
#	examples/imgui_impl_dx9.cpp
#	examples/imgui_impl_opengl2.cpp
#	examples/imgui_impl_opengl3.cpp
#	examples/imgui_impl_vulkan.cpp
#	imgui.cpp

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

Merge branch 'master' into docking ...

# Conflicts:
#	imgui.cpp
#	imgui_internal.h

Amend 48a09a7 with changelog, breaking changes, tweak demo code for spacing. (#2518)

Improved algorithm for mitre joints on thick lines

Popups: Closes popup at the time of FocusWindow(). Fixes right-click from closing all popups instead of aiming at the hovered popup level (regression in 1.67's ae76a1fd).

Merge branch 'master' into docking ...

# Conflicts:
#	examples/example_sdl_opengl2/main.cpp
#	examples/example_sdl_opengl3/main.cpp
#	examples/example_sdl_vulkan/main.cpp
#	examples/imgui_impl_sdl.cpp
#	examples/imgui_impl_sdl.h
#	imgui.cpp

Misc comments, internal renaming, added disable indentation option to Columns demo section.

Merge branch 'master' into docking ...

# Conflicts:
#	imgui.cpp
#	imgui.h

Added SetNextItemWidth() helper to avoid using PushItemWidth/PopItemWidth() for single items.

Demo: Documents: Fix misusage of ListBoxHeader().

Internals: Columns: Tweaks, renaming. Metrics: Show rectangles for child windows. ...

Renamed SameLine() first parameter.

Merge branch 'master' into docking ...

# Conflicts:
#	imgui.cpp
#	imgui_demo.cpp

Merged a bunch of small changes from Docking branch to reduce the difference between branches. ...

Noticeable: horizontal alignment of CloseButton. Menu fill take account of border. Various stylistic tweaks to accomodate other changes in Docking.

Merge branch 'master' into docking ...

# Conflicts:
#	imgui.cpp
#	imgui_internal.h

Internals, Docs: Added a bunch of clarification about ButtonBehavior in the form of a table (and to facilitate writing tests)

Merge branch 'master' into docking ...

# Conflicts:
#	imgui_demo.cpp

Demo: Comments, tweaks, removed some uses of ImColor helpers.

Merge branch 'master' into docking ...

# Conflicts:
#	examples/imgui_impl_dx9.cpp
#	examples/imgui_impl_opengl3.cpp

InputText: Work-around for buggy standard libraries where isprint('\t') returns true. (#2467, #1336) ...

Not using isprint. + todo items.

Examples: Vulkan: Added missing support for 32-bit indices (#define ImDrawIdx unsigned int). + demo typo

Renamed ImGuiDockNodeFlags_Dockspace to ImGuiDockNodeFlags_DockSpace for consistency. DockBuilderCopyDockspace() to DockBuilderCopyDockSpace(). Made casing consistent elsewhere. (#2109)

Docking: Renamed ImGuiDockNodeFlags_PassthruDockspace to ImGuiDockNodeFlags_PassthruCentralNode. + Comments, shallow tweaks. (#2109)

Docking: Fixed crash with ImGuiDockNodeFlags_AutoHideTabBar flag. (#2423, #2109)

Merge branch 'master' into docking ...

# Conflicts:
#	docs/CHANGELOG.txt
#	examples/imgui_impl_opengl3.cpp
#	imgui.cpp
#	imgui_internal.h

IsWindowHovered() made change which should have no effect in master but fix result of IsWindowHovered(ImGuiHoveredFlags_ChildWindows) over multiple viewport in docking branch. (#2432)