Story: Temperature Setter

[Yoric]

Meta-bug: #2 .

During the day, temperature of the heater should be set to 19C, but
during the night, reduce the temperature of heaters to 16C.

Can be expressed as

1. When the value of `a channel "get time of day" of service "foxbox clock"` is above 7pm do
    send `temperature: 16C` to `all channels "set temperature"`.
2. When the value of `a channel "get time of day" of service "foxbox clock"` is between 6am and 7pm do
    send `temperature: 19C` to `all channels "set temperature"`.

For a simple script like this, the "I need" part can probably be inferred from the actual triggers.

Getter channels

• We need a service "foxbox clock" with a getter channel "get time of day". This service is built-in the foxbox and does not need any discovery.

Setter channels

• We need services with channels that support "set temperature". The actual set of services is discovered dynamically, whenever we send the message, so as to support adding/removing heaters without having to alter the script.

Values

• Time of day. Represented in UTC, displayed in local time by the UX.
• Temperature. Represented in units, to avoid grave accidents.
• How do we handle overlapping intervals?

_edit_ Updated to Taxonomy API.