Changelog, minor tweaks. (#2585)

Examples: imgui_impl_osx: Added mouse cursor support. (#2585, #1873)

Update changelog, comments, made empty/no-text clipboard return NULL as with other implementation. Minor style tweaks. (#2546) ...

Fixed IMGUI_DISABLE_WIN32_FUNCTIONS not disabling IME code.

Add native mac copy/paste support to match win32 (#2546)

IO: changed AddInputCharacter(unsigned short c) signature to AddInputCharacter(unsigned int c). ...

Examples/Backends: Don't filter characters under 0x10000 before calling io.AddInputCharacter(), the filtering is done in io.AddInputCharacter() itself. This is in prevision for fuller Unicode support. (#2538, #2541)

Removed trailing spaces (#2038, #2299)

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

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

Internals: Replace unsigned short with ImWchar when dealing with character storage (missing cases) + in imgui_impl_ file keep using neutral type everywhere, added missing explicit cast in three bindings. (#2078)

Examples: imgui_impl_osx: Fix for incorrect DeltaTime calculation on mac OS. (#1978)

Apple: Fixed example_osx_opengl2, renamed to example_apple_opengl2 + misc comments

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

Examples: OSX: Added clipboard support. Fixed ignore list for xcode cruft. Comments about broken keys. (#1873)

Examples: OSX: Fixed obsolete enums. Fixed keyboard mapping. Added missing keyboard modifiers. (#1873)

Examples: Added imgui_impl_osx.mm bindings (#1870, #281)