Use AL Algorithm Instead of HA Transition for Sleep Mode

[pqhf5kd]

Currently AL sends a HA Transition to lights when Sleep Mode is turned on.

This presents two possible issues when using long transitions:
Some bulbs do not support long transitions
If I light is switched on during the transition, it will be in the target state.

If AL were to use it´s algorithm instead, these issues would be resolved.
I believe transition_color_temp_until_sleep does something similar, but it onlz works after somesun. Users may want to turn on sleep mode during the day .