Prepare google fonts

[dy]

Preparing for https://github.com/google/fonts/issues/4631

Related docs:

• PR docs
• Upstream repo structure
• Build the fonts
• Variable fonts
• Overall font requirements
• Font file requirements
• Static font specifics

Todo

• [ ] ? would it be easier to just merge wght PR first (seems useful) and proceed recreating from scratch?
• [ ] Read all Must-read docs
• [ ] Make sure files structure matches requirements
• [ ] Rename radi axis to SOFT
• [ ] Make sure building process is according to google docs
• [ ] Cover full latin range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+2074, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD
• [ ] Stub all non-glyph codes with blank space
• [ ] Cyrillic range for Centered 0..100 values U+0400-045F, U+0490-0491, U+04B0-04B1, U+2116
• [ ] Latin-ext range for Low-bound values U+0100-024F, U+0259, U+1E00-1EFF, U+2020, U+20A0-20AB, U+20AD-20CF, U+2113, U+2C60-2C7F, U+A720-A7FF;
• [ ] Update readme
• [ ] Update demo
• [ ] Make PR to google fonts