Meanwhile I bought a Raspberry Pi 3 as I was intrigued by all the projects people are showing on the web. I am not sure what I expected but what I have found is that the RPi is quite simply an outstanding and versatile piece of kit. So much so that I will be getting another one for the garage so I can search the web and listen to music as I work on the Seven. I have a PC there now but it is very old, a new cheap one would cost at least £150 to £250 to get something useful. But the RPi is a no brainer at £30 (+case +keyboard +mouse).
Within a few days of having the RPi I have managed to build (on a breadboard) and program an external lighting control system for my garden. This is something I was going to talk to Lutron or Helvar about with the hope of getting some end of line kit cheap. However with all the commercial lighting control kit out there it is the commissioning that costs money as you are not able to do it yourself. So the fact that a £30 RPi (and £10 of relays) can do everything I need and I can change the control via Python software is just fantastic.
When I wired the garden lights ~8 years ago I planed multiple circuits with the intention of controlling it via a simple system. As it is for 8 years we have controlled it all via a 20A DP switch in the kitchen. I will update this post once I hardwire the RPi into the garden lighting.
Screen shot of the Radiance Lighting Software (Bonus)
Garden Lighting Test Program