Initial fixes of common/config.go after rebase before refactoring of test-cases so that they don't require root to run.

common/config.go

@@ -8,6 +8,7 @@ import (
 	"regexp"
 	"strings"
 	"time"
+	"runtime"
 )
 
 // PackerKeyEnv is used to specify the key interval (delay) between keystrokes

common/config_test.go

@@ -7,6 +7,7 @@ import (
 	"path/filepath"
 	"strings"
 	"testing"
+	"runtime"
 )
 
 func TestChooseString(t *testing.T) {