Display SimHub values on buttons

[pre-martin]

It should be possible to display SimHub property values on Stream Deck buttons.

It should be possible to define the number of digits and a format, so that the implementation can chose a size for the digits, which just fits all digits on one button. E.g. a button, which displays only one digit could use a larger font size than a button which display values like 123 or 12.3.

A library for image drawing has to be chosen. https://devblogs.microsoft.com/dotnet/net-core-image-processing/ could be a starting point.