Some updates to satellite API

[dnmeid]

This PR:

• allows use of more than 32 buttons
• adds the text color if client requests colors (unfortunately the original API uses color for background color instead of bgcolor, so I use textcolor for text color instead of color)
• adds the option to read back colors in css rgb notation
• allows optionally to use button numbers in row/column format. The surface buttons start at 0/0 in that aspect, streamed button numbers are unchanged

API version is increased to 1.6.0
as clients are required to actually parse parameter names and not only rely on positions, I consider the addition of textcolor parameter not a breaking change

This PR also has a bunch of completely unrelated formatting

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[dnmeid]

all done and tested