Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_opengl3.cpp
#	imgui.cpp
#	imgui.h
#	imgui_draw.cpp
#	imgui_internal.h

Examples: include for intptr_t on tdm-gcc + mingw32 (#1936) + mouse buttons comments

Examples: OpenGL3: Added shaders more versions of GLSL + made the example app default to GL 3.0 + GLSL 130 (instead of GL 3.2 + GLSL 150) unless on Mac. (#1938, #1900, #1513, #1466, etc.)

OpenGL3: Added error output when shaders fail to compile / link. (#1938)

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Examples: Comments, Demo: Log early out, TODO. (#1553)

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Examples: Comments + shallow coding convention tweak to be consistent across examples and with imgui_impl_osx

Examples: Removed old example_apple/ + tweak comments (#1873)

Merge branch 'warrenm_osx'

Apple: Fixed example_osx_opengl2, renamed to example_apple_opengl2 + misc comments

Introduced a new Metal renderer implementation and a new example illustrating usage of Metal on macOS and iOS (partially addresses #1873)

Examples: Comments, bits of documentation

OSX: Various tweaks to imgui_impl_osx courtesy of @warrenm + fix NewFrame position which has been moved recently master. (#1873)

Merge branch 'master' into osx ...

# Conflicts:
#	examples/.gitignore
#	examples/README.txt

Ignore list: added emscripten output

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_glfw.cpp
#	examples/imgui_impl_glfw.h
#	examples/imgui_impl_sdl.cpp
#	examples/imgui_impl_sdl.h
#	examples/imgui_impl_win32.cpp
#	examples/imgui_impl_win32.h
#	imgui.cpp
#	imgui_internal.h

Examples: Ignore all *.user files (#1919) ...

For example `Qt Creator` create `CMakeLists.txt.user` file with user settings.

Examples: Comments to clarify how the keyboard data is indexed.

Fix include Example_glfw_vulkan cmake (#1916) ...

Probably got broken because of the refactor.

Fixed software Hand cursor from not actually working. Fixed demo from crashing. Fixed typo and extraneous trailing space. Added Changelogs. (#1913, #1914)

add hand cursor support (+11 squashed commit)

Examples: Apple: Fixed paths of GLFW+GL2 example. (#1906) Update ignore list.

Merge branch 'master' into viewport ...

# Conflicts:
#	imgui.cpp

Examples: OpenGL3: Remove misleading or unnecessary "#version 150" strings.

Examples: Fixes.

Fixed merge.

Merge branch 'master' into viewport ...

# Conflicts:
#	examples/imgui_impl_glfw.cpp
#	examples/imgui_impl_win32.cpp

Examples: Vulkan: nverted the parameters to ImGui_ImplVulkan_RenderDrawData() to be consistent with other bindings.

Examples: DirectX12: Moved the ID3D12GraphicsCommandList* parameter from ImGui_ImplDX12_NewFrame() to ImGui_ImplDX12_RenderDrawData() which makes a lots more sense. (#301)