Support Logger from logging as writer for Process from processmanager.

[rewenset]

Currently I've found solution to create wrapper for Logger such as:

type ProcessLogger struct {
	logging.Logger
}

func (pl *ProcessLogger) Write(p []byte) (n int, err error) {
	pl.Debug(string(p))
	return len(p), nil
}

and use this option when creating a new Process to set it for both out and err:

cn-infra/exec/processmanager/process_options.go

Lines 74 to 80 in 42c7431

	// Writer allows to use custom writer instance. Can be defined with nil parameters, in such a case
	// standard output will be used
	func Writer(outW, errW io.Writer) POption {
	return func(p *POptions) {
	p.outWriter, p.errWriter = outW, errW
	}
	}

It would be nice if this template code could be avoided.

I'm not sure if this requires changes in processmanager or logging packages.