Merge branch 'schneider/lodepng' into 'master'

.gitmodules

Documentation/conf.py

Documentation/index.rst

Documentation/pycardium/png.rst

bootloader/bootloader-display.c

epicardium/epicardium.h

epicardium/main.c

epicardium/modules/display.c

epicardium/modules/panic.c

hw-tests/dual-core/main.c

hw-tests/hello-world/main.c

hw-tests/ips/main.c

lib/gfx/framebuffer.c

lib/gfx/framebuffer.h

lib/gfx/gfx.c

lib/gfx/gfx.h

lib/lodepng/lodepng

lib/lodepng/lodepng.c

lib/lodepng/meson.build

lib/meson.build