update to 1.5.28
    
    - Allow query by code point even if Python’s unicodedata.name()
      does not know the character
    - Also read names from emoji-sequences.txt and emoji-zwj-sequences.txt
    - itb_emoji.py: Also read emoji-sequences.txt (from unicode.org)
    - Fix positioning of info popover (fix a typo in an “if” statement)
    - Show emoji properties from unicode.org when debugging is on
    - itb_emoji.py: Also read emoji-zwj-sequences.txt (from unicode.org)
    - Also use the emoji properties from unicode.org to decide whether
      to offer a lookup on emojipedia
    - Use property “Emoji_Modifier_Base” from emoji-data.txt to check
      whether an emoji supports skin tones
    - itb_emoji.py: Also read emoji-data.txt (from unicode.org)
    - Tentative skin tone support for families
    - Improve skin tone support: make it work for professions (roles) as well
    - Make skin tone popover scrollable and limit its maximum size