Better logging

A great suggestion! Untested code follows [cribbed some examples from the godocs]:
```
func NewOutputStream(name string) *io.PipeWriter {
    rd, wr := io.Pipe()
    go func () {
        scanner := bufio.NewScanner(rd)
        for scanner.Scan() {
            flog.Infof("[%s] %v", name, scanner.Text())
        }
    }()
    return wr
}
```