Simplified color handing (breaking change), pairing and improved docker files

Support and utility for pairing (commissioning) #114 (@chrysn)
Add Dockerfiles that work on Raspbian Stretch #116 (@tazle)
Simplified color handling #103 (@ggravlingen)

Please note that this release breaks functionality for some methods used to manage colors.

Add support for pairing

Support and utility for pairing (commissioning) #114 (@chrysn)

Cleanup on asyncio

#111 (@NovapaX)

Add validation for dimmer level

#109 (@lwis)

Fix max dimmer level and bump aiocoap to latest alpha

#105 (@lwis)
#107 (@lwis)

Bug fixes and expose Homekit ID

Update CLI to support 4.0 and expose Homekit key (#100)

* Update CLI to support 4.0
* Added Homekit ID
* Adding more tests for Gateway

Updated readme

Added security instructions.

Support for new DTLS identification method in latest gateway firmware

This release also contains changes to the way the API factories are created and used. Please refer to the updated examples, for examples on how to use these.

Fix of method set_predefined_color in device.py

#80

3.0.3

#75 Resolve issue with libcoap API (@rudyvan)