v1.13.0

• pay attention to the correct chroma sample positions
• heif_image now holds a list of decoding warnings
• use AOM AOM_USAGE_ALL_INTRA mode instead of AOM_USAGE_GOOD_QUALITY
• 'strict' decoding mode with more checks for standard conformity of input
• support for EXIF data >64k in JPEG output
• proper library initialization and cleanup
• separate quality settings for alpha channel (AOM)
• improve color conversion speed (no lroundf)
• build and packaging fixes