Add support for GARDENA mowers

[johan12345]

Gardena, a subsidiary of Husqvarna, also has a few robotic lawn mowers, mainly for smaller gardens. Some of them are also compatible with the "smart system" for controlling them through Gardena's app.

The app uses the same API as Husqvarna for login (_API_IM), just a slightly different API for the actual controlling of the mower (_API_SG). I adjusted pyhusmow so that it should be able to control both types of mowers now, and tested it with a Gardena "smart Sileno City".

The Gardena mowers don't have a GPS for tracking, so the geo_status function raises a CommandException in that case.

[chrisz]

Hi @johan12345,

Thanks for the patch but maybe it would be better to have two separate project: one for husqvarna and one for gardena. I think there are enough differences to justify the split.

I don't think people who have several automowers choose two different brands so it's not a problem to have two different projects.

The code already needs a big clean up and I'm afraid to encounter problems to maintain the code with more options (in case of change, I can't check if gardena support is not broken).

If it's ok for you, maybe I could add a link in the readme to your project.

Chris