Log Message:
public-sans: update to 2.001.

Public Sans v2.001:

General:
- Fixed style linking in stat table
- Update to 2.001

Public Sans v2.000:

General:
- Rename `PublicSans-italics` to `PublicSans-Italic`
- Fixed language feature encoding
- Update to 2.000

Glyphs:
- Modified `eth` contours
- Adjusted curves of `S` and `Thorn`
- Corrected
  - `Eng`, `eng`
  - `Ldot`, '`ldot`
  - `Tbar`, `tbar`
  - `gcommaaccent`
- Removed unnecessary anchors
- Decomposed and transformed components
- Corrected dot accent position in thin masters
- Slightly shifted position of `acute` and `grave`
- Adjusted percent and perthousand
- Corrected positon of `caron.alt`
- Added caret anchors
- Corrected Naira currency
- Decomposed nested components
- Corrected kerning group inconsistencies in caps and lowercases
- Corrected position of `breve_hookabove`
- Adjusted alignment zones
- Renamed narrow acutecomb variants `acutecomb.001` to `acutecomb.narrow`
- Added `gravecomb.narrow`
- Fixed contour directons
- Added `_ringacute` in `aringacute` italic, decomposed and merged
  `_ringacute`
- Decomposed overlapping components

Structure:
- Renames `/src` directory to `/sources`, which includes the build script
  and the Glyphs sources
- Renames `/binaries` directory to `/fonts` adding TTF fonts as a
  `/fonts/ttf` directory separate from webfonts
- Adds `AUTHORS.txt` for copyright-holding authors
- Adds `CONTRIBUTORS.txt` for contributors who are not copyright authors
- Adds explicit description file
- Adds `requirements.txt` for python 3.x `pip3 install -r requirements.txt`
- Moves old version binaries to an `/old` directory
- Removes dash from `Public-Sans` in source files to `PublicSans`

Build:
- Add weight class fix in build script
- Added new fontbakery tools to `requirements.txt` and build script
- Uses new locations
- Removes autohinting
- Updates build process to build with Docker
- Adds gftools gen-stat to the build process, as well as a stat.yaml file