I get "Option 'version' is unknown" if it comes after other user-defined options on the command line

Since `version` is pretty much built-in, it should never be "unknown", especially if this message is immediately followed by helptext that clearly shows that it is a valid option.

```
3676 ~/fork/foo-etl$ dotnet etl/bin/Debug/netcoreapp3.0/etl.dll -c foo -d bar --version
etl 0.0.1
Copyright (C) 2020 etl

ERROR(S):
Option 'version' is unknown.

-c, --configdir Required. Path to dir that contains client configurations

-d, --invoicedir Required. Path to dir that contains invoices are

--help Display this help screen.

--version Display version information.
```

Reproduce the reported `dotnet` command with `--version` after the user-defined options `-c` and `-d`. Trace how the command-line parser handles the built-in version option and add a regression test for this ordering; done means the version is displayed without an "unknown" error.

Written by the indexing model from the issue text.