Enables the Fan interface for devices supporting that component.
Currently the only device with a fan is the ks240 which implements it as
a child device. This PR adds a method `get_module` to search the child
device for modules if it is a WallSwitch device type.
In order to support the ks240 which has children for the fan and light
components, this PR adds those modules at the parent level and hides the
children so it looks like a single device to consumers. It also decides
which modules not to take from the child because the child does not
support them even though it say it does. It does this for now via a
fixed list, e.g. `Time`, `Firmware` etc.
Also adds fixtures from two versions and corresponding tests.
Allow controlling the color temperature via features interface:
```
$ kasa --host 192.168.xx.xx feature color_temperature
Color temperature (color_temperature): 0
$ kasa --host 192.168.xx.xx feature color_temperature 2000
Setting color_temperature to 2000
Raised error: Temperature should be between 2500 and 6500, was 2000
Run with --debug enabled to see stacktrace
$ kasa --host 192.168.xx.xx feature color_temperature 3000
Setting color_temperature to 3000
$ kasa --host 192.168.xx.xx feature color_temperature
Color temperature (color_temperature): 3000
```
