Issue #19 - Net 8 support

[nyetwurk]

Issue #19

@ljscodex Can you review https://github.com/NefMoto/NefMotoOpenSource/issues and see which ones of those this addresses?

Specifically
#1 , #7 , #8 - various build issues (including trying to build it under CI)
#2 , #16 - baudrate, support other cables etc.

[nyetwurk]

@NefMoto can you review this or should I just merge?

[ljscodex]

hi @nyetwurk, @NefMoto the changes will only convert to make the application NET8 or newer compatible, a new thread handler was added to replace the previous Async and delegates functions.

So, at the moment the only issue we can mark as done/close is the 19#