Allow for templates in configuration

[claytonjn]

E.g. allow max_brightness to be set from an input slider, etc.

https://community.home-assistant.io/t/circadian-lighting-custom-component/61246/530

[nightcat91]

+1
I think this would be a great addition

[Heronimonimo]

+1 :)

[stigvi]

Are anyone working on this feature? If not, I could give it a try and make a pull request if there is interest in it.

[stigvi]

I have already a working version with support for templates. Will test it more and make a pull request in a few days.

[banaslee]

@stigvi I saw your PR #66 and because is from April I'm wondering if you think is stable enough for others like me to give it a try. I was currently trying to set a template minimum brightness and came across this issue and your PR.

Also, commenting on this issue so watchers can see some action, since there was no mention of your PR here.

[stigvi]

It was working and probably still is, but recently HA has changed regarding how to extract entities from a template and the method PR 66 is calling is now deprecated and should be replaced with the new one.

I am not using circadian lighting anymore. I had some serious deconz problems a few months back and constantly changing the light made a to much load on the system. That is solved now, but I have found that making some scenes and automatically activate them based on sun position and other factors, are more flexible for me than circadian lighting.