updated to version 2.0.0
see installed CHANGELOG.md
## 2.0.0

- Release 2.0.0
- Supports Ruby 3.0

## 2.0.0.pre2

- Update 2.0 branch to Unicode 13

## 2.0.0.pre1

Will be published as non-pre version on rubygems.org when Ruby 3.0 is released (December 2020)

- Introduce new class-based API, which remembers your string-width configuration. See README for details.
- Remove auto-loading of string extension
- You can: `require "unicode/display_width/string_ext"` to continue to use the string extension
- The manual opt-out `require "unicode/display_width/no_string_ext"` is not needed anymore and will
issue a warning in the future
- Remove (already deprecated) String#display_size and String#display_width aliases

Refactorings / Internal Changes:

- Freeze string literals
- The Unicode::DisplayWidth now is class, instead of a module, this enables the new config-object API