Log Message:
cascadia-ttf: update to 2106.17.

Features:

- Arabic (and Urdu) support added (design by Mohamad Dakak) (#84)
    - See the Arabic features PDF for the exciting new Arabic ligature
      functionality used in Cascadia Code that gives the font greatly improved
      readability and feel more more akin to a text typeface.
    - Don't want all that? Don't worry, Cascadia Mono will house a normal
      version of Arabic.

- Hebrew support added (design by Liron Lavi Turkenich) (#465)

- Due to popular demand, we've introduced a more "toned-down" version of
  Cascadia Italic, which does away with a number of the cursive letter forms.
  (#468)
    - Entry and exit strokes across the italic lowercase have been rounded
      to better achieve the fun / playful design language that we intended
      for the italic. Other skeletons have been modified as necessary.
      Cyrillic has also been updated for better consistency with the new
      design.
    - You can now activate the original cursive versions of /f /l /s and
      /r with typographic feature salt or ss01.

Changes:

- We have adjusted the slant on all of the italic letters to make sure it's
  consistent (#470)
- Italic Only: #507 - bar and broken bar will now stay upright for better
  clarity
- Fixing a bug in the ccmp feature file and added ccmp to the feature
  set in the build script.
- Deleting the (unused) liga feature file
- Vika has reviewed and improved some forms in Cascadia Code upright.
- Greek lowercase has been updated per feedback from Gerry Leonidas to
  be more cohesive (No longer a mix between a "Monday" and \ 
"Friday" font.
  All Friday, all the time!)
- #422 - Bitcoin glyph added
- #427 - FFFD glyph added
- #418 - top bar corrected
- #433 - hinting corrected to ensure alignment
- #435 - adds consistent ligature form for =>> <<= =<< and
  >>= (the infinite arrows still work with addition of more equals)
- #443 - ligature now ignores (*) scenario
- #454 - adds ignore to prevent equal_equal ligature from showing up
- #467 - Not specifically sure of the problem here, but suspect that it will
  be fixed with this - update.
- #477, #478, #479, #480 - interpolation issues fixes in a lot of ligatures
- #481 - JetBrains enumerates fonts weird. We've modified the internal naming
  so that it will register Cascadia Code correctly. Also aligned postscript
  naming with Google's recommendation, so will show up as "Regular" \ 
instead of
  "Roman".
- General improvement of weight balancing
- Weight of lowercase rounds reduced in the Bold weight in Cascadia Code.
- Weight of Capital stems increased in Extralight weight in Cascadia Code.
- Tweaked weight of ogonek in ExtraLight.
- Added a localized form for ij and IJ should a user chose to use those
  codepoints and want an accented version.
- Split fraction bar at heavier weights to improve clarity of fractions.
- Adjusted standard box drawing characters to align with GDI metrics, and added
  a complete set of DWrite-specific ones that align with sTypo (using rclt).
- Ironed out some tiny inconsistencies in the <$ $> <$> ligatures which
  we suspect no one will ever notice.
- Fixed centering of braces and some hyphens.
- Fixed inconsistency between semicolon/colon and period weight in bold. Also
  fixed slight differences in hyphen-like glyphs in bold. You're as surprised
  as we are.
- Increased weight of underscore in bold.
- Changed design of commaaccent, commaaccentmod commaturnedabove and commaabove
  to be more distinguishable (following design of quotes).
- Fixed descents of various greek lowercase glyphs that were inconsistent.
- Felt ligated, might edit later.
- Corrected some additional interpolation bugs