Cldr Messages version 1.0.0

Since the API has been stable for over a year, this becomes the 1.0 release.

Bug Fixes

• Fix Cldr.Message.Print.to_string/2 to force a deterministic order of choices.

• Fix extracting variable bindings from simple_format. Thanks to @AlexisChavez97 for the report and the PR. Closes #16.

• Bump Elixir minimum required version to 1.11 to match the rest of ex_cldr.