v4.0.0-pre

What's Changed

• Warn on use of deprecated elements, functions and properties by @keithamus in #217

BREAKING CHANGES

This PR is a BREAKING CHANGE, in which we console.warn on all deprecated features, which we plan to remove in the next version, v4.0.0.

The following features are to be deprecated in v4.0.0:

• The local-time element will be removed.
• The time-ago element will be removed.
• The time-until element will be removed.
• getFormattedTitle will be private.
• getFormattedDate will be private.
• format will no longer accept a strftime compatible format. Instead, any value other than 'micro', 'elapsed' will revert to the string 'auto'
• the Intl.DateTimeFormat constructor will not be ponyfilled, and so in environments without this constructor, the
  element will fall back to provided text.
• the Intl.RelativeTimeFormat constructor will not be ponyfilled, and so in environments without this constructor, the element will fall back to provided text.

v4.0.0-pre maintains compatibility with Version 3 but will console.warn on the use of any of these deprecated features. Additionally the typescript definitions have changed which means integrators will need to alter their code for typescript.

v4.0.0-pre will allow integrators to install a version and ship it to production in a backwards-compatible way with v3.x, while refactoring out any uses of deprecated APIs, before finally installing v4.0.0.

Full Changelog: v3.6.0...v4.0.0-pre