sdl2: start to write a new window provider based on sdl2. sdl2.pxi has been created from the ignifuga game engine, but maybe functions and definitions are missing. Need to create a generator out of it. At some points, window_sdl (used currently only on iOS) should be removed.)
sdl2: add missing window_sdl2 files, and correctly implement 'auto' fullscreen. read all the missing window event too.
sdl2: add sdl2 image core provider (not complete, need more conversion format, and save support)
sdl2: support for text rendering
sdl2: ignore generated .c
sdl2: fix ignore
sdl2/text: fix color bgra -> rgba
core:sdl2 clipboard provider
Merge branch 'master' of https://github.com/kivy/kivy
Merge remote-tracking branch 'upstream/master'
Make mouse simulated mutli-touch optional.
Add docs, only provide sim if initiated so.
Make scatter always use simulated multitouch.
Don't overwrite previous profile.
fix for #2129
Add config callback to change the log file when the config log_dir/log_name change.
Create log_dir path directories recursively

This change will create the custom log folder and its parents, if needed, in the case of using absolute paths too.
Doc fix: clearify that alias prop setter returns True to cause dispatch.
Copy observers list when dispatching to prevent observers from being eaten.
Add rebind option to Property to allow dynamic rebinding of properties in kv.