Internals: Removed unused internal variant of ArrowButton().

Fixed a few zealous warnings.

Fixed unused variable warning.

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_dx10.cpp
#	examples/imgui_impl_dx11.cpp
#	examples/imgui_impl_dx12.cpp
#	examples/imgui_impl_dx9.cpp
#	examples/opengl2_example/imgui_impl_glfw_gl2.cpp
#	examples/opengl3_example/imgui_impl_glfw_gl3.cpp
#	examples/sdl_opengl2_example/imgui_impl_sdl_gl2.cpp
#	examples/sdl_opengl3_example/imgui_impl_sdl_gl3.cpp
#	examples/vulkan_example/imgui_impl_glfw_vulkan.cpp
#	imgui.cpp
#	imgui.h
#	imgui_internal.h

Style: Default style is now StyleColorsDark()! Toward a 1.60 release :) (#707)

IO: ImGuiConfigFlags_NoMouse disable hovering so it is not destructive. Amend 2464e62

NewFrame: Extract some code into a NewFrameUpdateHoveredWindowAndCaptureFlags() which can be of use with touch-based inputs systems.

Comments about io.WantCapture flags + todo entries.

NewFrame: Extract some code into a NewFrameUpdateMouseInputs function. Moved settings saving higher up in the function so it is next to its peers.

IO: Added ImGuiConfigFlags_NoMouse to force clear/disable mouse inputs in NewFrame().

Renamed ImGuiConfigFlags_NoSetMouseCursor to ImGuiConfigFlags_NoMouseCursorChange. Followup to 75c3793 two weeks ago. (#787, #1495, #1202) + comments

Columns: Fixed calling Columns() again with the same number of columns. (#125)

Viewport, Platform, Examples: Added support for transparent window via PlatformIO Platform_SetWindowAlpha (#1542) + fixes for GLFW 3.3

Viewport: Comments about honoring ImGuiViewportFlags_NoInputs and MouseHoveredViewport. (#1542)

Viewport: Moving a window accross viewports tries to preserve the dragging pivot (that is assuming that the window will be evenly scaled by DPI, aka Style is scaled). (#1542)

Viewport: Renamed RenderPlatformWindows() to RenderPlatformWindowsDefault(), tweaked examples and emphasis optional Viewport code path. (#1542)

Contribution guidelines

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_dx10.cpp
#	examples/imgui_impl_dx11.cpp
#	examples/imgui_impl_dx12.cpp
#	examples/imgui_impl_dx9.cpp
#	examples/opengl2_example/imgui_impl_glfw_gl2.cpp
#	examples/opengl3_example/imgui_impl_glfw_gl3.cpp
#	examples/sdl_opengl2_example/imgui_impl_sdl_gl2.cpp
#	examples/sdl_opengl2_example/imgui_impl_sdl_gl2.h
#	examples/sdl_opengl3_example/imgui_impl_sdl_gl3.cpp
#	examples/sdl_opengl3_example/imgui_impl_sdl_gl3.h
#	imgui.cpp

Hide new windows for one frame until they calculate their size. Also fixes SetNextWindowPos() given a non-zero pivot. (#1694)

Internal: using more consistent comparaison with HiddenFrames to not imply it could be -1. Tweaked comments.

Added extra comments and assertions to avoid user combining ImGuiCond flags. (#1694)

Tooltip windows uses PopupBorderSize (#1697) + commented out debug stuff.

README.md: add link to Gallery Part 6

Removed need for -Wnocast-qual on modern Clang/Xcode as a token of good behavior. Unfortunately the old stb_ decompress code is a little const clunky. + warning fix in stb_textedit which is already in master afaik.

BeginChild: named child don't include the full id inside their name (#1698)

Fixed Clang zealous cast-call warning (on par with GCC) which decided to warn against explicit C-style casts now.

Comments

Comments, FAQ

Examples: Tweak comments. (#1704, #1708).

Examples: Win32: Fixes for MingW which doesn't support a 2007 define? I have no idea why people still use MingW (#1704, #1463)