Zigpy-znp

Changes

- Add the coordinator itself to the device list, allowing Zigbee groups to work in HA after a restart (issue 27)
- Rewrite HA custom component to inject much earlier and thus more reliably (234b1f2925b31281a8da888436ede4984162a40c).
- Condense all unnecessary endpoints into a single endpoint with multiple in/out clusters (0b6100cb25552b0fe7777300f6fa847f5a8e9aa4).
- Remove the custom `TRACE` log level and instead use `DEBUG` (e9c1aef941eac5cc2ae7613799fa270061fd4463).
- Add a converter for `ZDOCmd.Mgmt_Permit_Joining_req` and an explicit error message for missing converters (65269da61f7cb93f0268dc84bfed654169cb782c).
- Support both old- and new-style zigpy structs (https://github.com/zigpy/zigpy/pull/440)

Global changes
- Support Zigbee groups and multicast requests
- Expose the current Zigbee channel on startup, not just the channel mask.
- Implement LED control. Set it with `led_mode: one of (off, on, blink, flash, toggle)`

Preliminary CC2531 support!
- Network formation and simple commands have been superficially tested
- Validate binary firmware CRCs before firmware flashing with `python -m zigpy_znp.tools.flash_write`
- Skip the 60 second bootloader delay
- Support NVRAM backup/restore. *Warning: don't mix CC2531 backups with ZZH and LAUNCHXL backups. It will not work and you might softlock your device and need to reflash.*

Changes

* Add OTA update support.

Changes

* Read current logical channel on startup. Can be accessed with `app.channel`.
* (Experimental) Allow setting the current logical channel directly in the NIB.
* Allow optional schema parameters for variable-length Z-Stack commands.
* Rename NVRAM commands to `nvram_read` and `nvram_write`.
* Implement flash reading and writing for CC2531:

bash
$ python -m zigpy_znp.tools.flash_read /dev/serial/by-id/radio -o flash.bin
$ python -m zigpy_znp.tools.flash_write /dev/serial/by-id/radio -i flash.bin

Changes

- Add omitted `coloredlogs` dependency for NVRAM backup and restore commands.

Changes

- Add installation instructions for Home Assistant to README.
- Implement NVRAM backup and restore commands.
- Fix network formation bugs.