changed os check to compile time

[AmeyaPurao]

No description provided.

[mymindstorm]

I like the *_linux.go and *_windows.go. We can ditch the windows/ and linux/ dirs.

The entrypoint (triage/triage.go) should not be platform specific. I feel like this moves us too close to the direction of having two different programs in one codebase. For triage, we are collecting the very similar information across both platforms, it's just that we use different methods to collect that information per-platform. For example:

// triage.go

func Run() {
  var err Error
  err = printUsers()
  err = printIpv4()
  // ...
}

// users_linux.go
func printUsers() { /* ... */ } 

// users_windows.go
func printUsers() { /* ... */ }