ImGuiTextBuffer: Avoid heap allocation when empty.

Comments + internal using Tab Stop terminology (ImGuiItemFlags_NoTabStop instead of !ImGuiItemFlags_AllowKeyboardFocus)

Viewport: Added ImGuiConfigFlags_ViewportsDecoration to re-enable platform decoration (#1542)

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Drag and Drop: Added GetDragDropPayload() to peek directly into the payload (if any) from anywhere. (#143)

Fix missing IMGUI_API and mismatching namespace internal's CreateNewWindowSettings (#2105)

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_win32.cpp
#	examples/imgui_impl_win32.h
#	imgui.cpp

Renamed SetScrollHere() to SetScrollHereY(). Kept redirection function (will obsolete).

BeginChild(): Fixed BeginChild(const char*, ...) variation erroneously not applying the ID stack to the provided string to uniquely identify the child window. This was undoing an intentional change introduced in 1.50 and broken in 1.60. (#1698, #894, #713) + reworked the Begin/BeginChild comments in imgui.h.

ImVector: Fixed a oddly unqualified return type in the assignment operator (I assume C++ handles it nicely as this never warned anywhere, but it is completely unintentional).

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_dx9.cpp
#	examples/imgui_impl_opengl2.cpp
#	examples/imgui_impl_opengl3.cpp
#	examples/imgui_impl_vulkan.cpp

Internals: Replace unsigned short with ImWchar when dealing with character storage. (#2078)

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp
#	imgui_internal.h

Version 1.66 WIP

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Version 1.65

Viewport: Making the code a little more sturdy (flag changes) + added descriptions. (#1542)

Merge branch 'master' into viewport + added viewport ConfigFlags/BackendFlags ...

# Conflicts:
#	imgui.cpp
#	imgui.h

Nav: Removed the [Beta] tag from various descriptions of the gamepad/keyboard navigation system. Although it is not perfect and will keep being improved, it is fairly functional and used by many. (#787)

Renamed io.OptCursorBlink/io.ConfigCursorBlink to io.ConfigInputTextCursorBlink. (#1427) + changed ImGuiIO layout.

Demo: Added a "Configuration" block to make io.ConfigFlags/io.BackendFlags more prominent.

Minor mostly inconsequential merges from Viewport + LoadIniSettingsFromMemory() entirely skip lines starting with ';'

Minor inconsequential merges from Master/Docking branches

Merge branch 'master' into viewport

Version 1.65 WIP

Merge branch 'master_164' into viewport_164 ...

# Conflicts:
#	imgui.cpp
#	imgui_draw.cpp
#	imgui_widgets.cpp

Version 1.64

Version 1.64 WIP

Version 1.64 WIP

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/example_glfw_opengl3/main.cpp
#	examples/imgui_impl_opengl3.cpp
#	imgui.cpp
#	imgui_internal.h