v0.9.0-pre14

AVIF: Added AVIF image format
BINDINGS/C++: Added more consts
BINDINGS/C++: Added more image() constructors
BINDINGS/C++: Avoid starting conflicting reading and writing operations
BINDINGS/C++: Refactor image_reader and image_writer
BINDINGS/C++: Update docs
COMMON: Added TRACE log level
COMMON: Added YUV pixel formats
COMMON: Added chroma_subsampling in source_image
COMMON: Move memory allocation functions into memory.h
COMMON: Remove EXIF codec feature
COMMON: Remove animated property. Use delay instead
COMMON: Remove redundant examples
COMMON: Update 'A structure' -> specific structures names
DOC: Added note on brew and updated 'brew install' command with new prefix
EXTRA: Update libs
GIF: Remove redundant check for NULL after malloc
LIBSAIL-MANIP: Fixed assigning YCbCr pixels from uint16 values
LIBSAIL: Added ?? pattern support in magic numbers
LIBSAIL: Added missing extern
LIBSAIL: Avoid dlsym in combined mode
LIBSAIL: Fix signed/unsigned mismatch
LIBSAIL: Fixed sscanf argument to use &
LIBSAIL: Make codecs info as an exported variable to avoid dlopen/dlsym
LIBSAIL: Moved functions pointers to v5_pointers.h
PNG: Allocate text lines in heap
SAIL: Added macOS 11.3 in Travis
SAIL: Fix Debian control installation rules
SAIL: Fix SAIL non-VCPKG build with SAIL_COMBINE_CODECS=ON
SAIL: Install sail-codecs CMake configs in a separate directory
SAIL: Remove macOS 10.14 from Travis to save some Travis credits
TESTS: Avoid side effects in munit_assert()
TESTS: Fix linking order in static mode
TESTS: Fixed minor memory leak in sail-dump
TIFF: Use uint32_t instead of deprecated uint32 from tifflib