func (t *Task) SetInitFunc(f TaskFunc) {
	t.init = f
}
SetInitFunc sets the TaskFunc which is executed before the main TaskFunc. It's
pupose is to do any setup of the DockerClient which depends on command line args
for example
package cali
import (
	"fmt"
	"os/user"
	"path/filepath"
	"strings"
	log "github.com/Sirupsen/logrus"
)
type TaskFunc func(t *Task, args []string)
var defaultTaskFunc TaskFunc = func(t *Task, args []string) {
	if err := t.SetDefaults(args); err != nil {
		log.Fatalf("Error setting container defaults: %s", err)
	}
	if _, err := t.StartContainer(true, t.Name); err != nil {
		log.Fatalf("Error executing task: %s", err)
	}
}
type Task struct {
	f, init TaskFunc
	*DockerClient
	Name string
}
func (t *Task) SetFunc(f TaskFunc) {
	t.f = f
}