Added Multiple Target Frameworks to CLI projects

[tthiery]

• Fixed Examples, CLI, TestScript Projects
• Fixed the documentation

155 breaking

[tthiery]

@dkurok Can you have a look into this?

This approach multi-targets the command line projects. it has the disadvantage of requiring more command line parameters for normal use (e.g. dotnet tool install -g --framework .... and dotnet run -f xxx -- device list) but it brings tons of benefits

• Multiple adapters are compiled into the solution
• Linux works with the CLI projects (especially upcoming bluez)
• We get as a side job a powerdup.json support.

I basically took the benefits of the other PR while using multi-targeting instead of plugin loading.