Bellows

Configure Link Key Number depending on protocol version.

Changes

- Allow establishing of TC link keys Adminiuga (208)

Changes

- Create Contributors.md file with list of contributors Hedda (203)
- Added a "How to contribute" section to README.md Hedda (204)

🚀 Features

- Implement Zigbee source routing. Adminiuga (205)

Breaking
- Drop python 3.5 support (198)

New features
- Group multicast requests support (199)

Fixes
- Fix permit with install code (197)
- Configure end device poll timeout depending on version (195)

Changes
- Adopt black code formatting (200)
- Adopt release drafter (201)
- Increase pan_id conflict reporting threshold (194)
- Readme updates (190)

Breaking
Sync up with [Zigpy 0.9.0 Release](https://github.com/zigpy/zigpy/releases/tag/0.9.0) `zigpy==0.9.0` is the minimum required version onward.

Changes
- `handle_join()` on receiving ZDO Device Announce requests (https://github.com/zigpy/bellows/pull/186)

Fixes
- don't use extended timeouts when sending a reply message