Inconsistent arg and option naming convention

Looking at the outputs of `dotnet package -h`, `dotnet tool -h`, `dotnet format -h`, I see various arguments and options using UPPER_CASE, PascalCase, camelCase, skewer-case. In examples like `dotnet package -h` and `dotnet tool -h` where different sub commands use different conventions, the help page looks a little jarring in my opinion. I didn't check all the dotnet SDK commands, so there might be more than the examples than what I provided above.

I think the SDK should define a convention and all first-party commands should try to standardize on it.