Address Ubuntu Error with Agent

[RecursiveProgrammer]

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Minor updates: Added a makefile to help me compile the Agent: you can ignore this file if you prefer. I also was receiving an error with '& disown'. This may be specific to Ubuntu, though. I am not sure how I would create a Unit test to show the error while connecting to the client machine. I will keep an eye out for tutorials on what needs to be done to create unit tests.

[bitbound]

The arguments aren't throwing. They're just being logged as unrecognized parameters, because I added them after the command line parsing stuff and haven't updated it to ignore them. That's why they're written as Info level.

2021-03-09 07:36:31.832 [Info] Command line arguments are invalid.  Key: &
2021-03-09 07:36:31.832 [Info] Command line arguments are invalid.  Key: disown

Without disown, the new process (e.g. the desktop app that captures the screen) would exit as soon as the thread that spawned it is terminated. I don't know if that's changed in .NET 5, but I wouldn't remove it for the sake of removing a couple log entries.

[bitbound]

I tested this briefly, and it seems to be working.

Could you please test chat and unattended remote control on Ubuntu and Manjaro, and let me know that it's all working?

Thanks. :)

[RecursiveProgrammer]

Using manjaro and XFCE: Appears to be working. Disconnected and reconnected without the agent losing connection. Chat seems to be working on both. I did see an error on Manjaro involving binding to Avalonia.Controls.Button.CommandParameter: Null value in expression ''.' . I think this message is appearing in the current build, as well. I shall look into what is causing this message, next.

[bitbound]

Awesome. Much appreciated.

Yeah, that XAML binding error was pre-existing. If you want to look into it, that'd be cool, but it doesn't affect this PR.

I'll merge this in when I get off work.

Thanks!