v2.5.0: Add support for regional KuCoin EU & EU REST APIs & WebSockets

What's Changed

• feat(v2.5.0): support regional KuCoin EU and AU REST APIs and WebSockets by @tiagosiebler in #116
• Add readme notice on upcoming migration to the Siebly.io GitHub organisation.

Full Changelog: v2.4.1...v2.5.0