Added Z-Wave K8 scene controller

[haraldpaulsen]

Blueprint Checklist

• [x] You viewed the README and conformed to the naming conventions
• [x] You ordered the actions as stated in the README action order
• [x] All filenames are lowercase and uses '-' for spaces and not '_' while using {service-name}-{switch-name-or-type}.yaml format
• [x] Images are png
• [x] Image backgrounds are transparent and is cropped to the device boundries
• [x] Images has a maximum width of 800px and maximum height of 500px
• [x] There are no missing buttons or actions
• [x] Your integration/service is running on the latest version
• [x] You have tested your blueprints and made sure each button and action works

[haraldpaulsen]

K8 is a Z-Wave scene controller made my Sunricher as OEM for other companies. In Norway it is marketed as Namron K8 and Heatit Z-push button 8, and it comes in white or black. I kept the name generic.

They also make a K4 and K2 with 4 respectively 2 buttons. There are also Zigbee versions but that is not relevant to this pull request.

[Sian-Lee-SA]

Thank You