Merge branch 'master' into viewport ...

# Conflicts:
#	examples/example_sdl_vulkan/main.cpp
#	examples/imgui_impl_dx11.cpp
#	examples/imgui_impl_dx12.cpp
#	examples/imgui_impl_glfw.cpp
#	examples/imgui_impl_sdl.cpp
#	examples/imgui_impl_vulkan.h
#	imgui.cpp

Removed trailing spaces (#2038, #2299)

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_win32.cpp

Examples: Win32: Added support for mouse buttons 4 and 5 via WM_XBUTTON* messages. (#2264)

Examples: Win32: Fix for older Windows SDK.

Merge branch 'master' into viewport ...

# Conflicts:
#	docs/CHANGELOG.txt
#	examples/imgui_impl_win32.cpp
#	imgui_demo.cpp

Examples: Win32: Using IsChild() to be compatible with windows created within a parent. (#1951, #2087, #2156, #2232)

Merge branch 'master' into viewport ...

# Conflicts:
#	docs/CHANGELOG.txt
#	examples/imgui_impl_win32.cpp
#	examples/imgui_impl_win32.h

Examples: Win32: Added support for XInput games (if ImGuiConfigFlags_NavEnableGamepad is enabled).

Examples: Win32: Using GetForegroundWindow() instead of GetActiveWindow() to be compatible with windows created in a different thread. (#1951, #2087, #2156, #2232) [many people]

Viewport: Added ImGuiWindowClass / SetNextWindowClass() (concept imported from Docking ImGuiDockFamily), which currently allows to overwrite viewport flags on a per-window basis. Exposed FindViewportByID(). Win32: Support for ParentViewportId. (#1542)

Viewport: Win32: Workaround to the fact that ::WindowFromPoint() seems to return Windows using ImGuiViewportFlags_NoInputs / HTTRANSPARENT when dragging nearby the platform title bar. This is to allow using platform decoration. I don't understand this well atm. (#1542)

Viewport: Added Platform_UpdateWindow hook for general purpose: Rework Win32 code to reflect viewport flags changes into Win32 while the window is active.

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_sdl.cpp

Tweaked asserts

Viewport, DPI: Now using DpiScale from the ImGuiPlatformMonitor array instead of calling Platform_GetWindowDpiScale() before the platform window creation. Might even tentatively see if things work out without Platform_GetWindowDpiScale. (#1676)

Viewport: Win32, GLFW, SDL: Clarified back-ends by using global mouse position direction. GLFW: disabled io.MouseHoveredViewport setting under Mac/Linux. (#1542, #2117) + various comments.

About, IO: Added io.BackendPlatformName, io.BackendRendererName for informational/QA purpose.

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_dx10.cpp
#	examples/imgui_impl_dx11.cpp
#	examples/imgui_impl_glfw.cpp
#	examples/imgui_impl_opengl2.cpp
#	examples/imgui_impl_opengl3.cpp
#	examples/imgui_impl_sdl.cpp
#	examples/imgui_impl_win32.cpp
#	imgui.h

About, IO: Added io.BackendPlatformName, io.BackendRendererName for informational/QA purpose.

Viewport: Added support for minimized window which caused problem when ImGuiBackendFlags_HasMouseHoveredViewport was not supported. (#1542) + todo

Examples: Win32: Handle UTf-8 in platform window title setting. (#2164)

Merge branch 'master' into viewport

Merge branch 'master' into viewport ...

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

Examples: Referring to missing gamepad support in back-end that are missing it.

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

Examples: Using "dear imgui" terminology in all examples headers/comments + fix minor typo.

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_opengl2.cpp
#	examples/imgui_impl_opengl3.cpp
#	imgui.cpp

imgui_impl_win32: Don't redefine WIN32_LEAN_AND_MEAN if already defined (#2014)

Viewport: Removed the need for the back-end to fill io.MousePosViewport, it seems unnecessary at this point. (#1542)