Disable yaml case until test can be rewritten

show_test has been failing intermittently since
af3f0f6c introduced `-f`.

The test failure is due to the flags not being completely reset
between `RootCmd.Execute()` invocations, thus the second of json/yaml
(changes because hash ordering) sees *duplicate* `-f` options, and
produces duplicate output.  This breaks json test validation, but
not yaml(!)

Ideally we would revert the offending change and resubmit with fixed
tests, but there have been numerous changes merged since. To stop
developing _further_ failure blindness, this change simply disables
the (less-strict) yaml testcase while a rewrite of show_test is
undertaken (probably a move to new integration framework).

This is *not* a fix for #99

cmd/show_test.go

@@ -22,8 +22,6 @@ import (
 	"path/filepath"
 	"reflect"
 	"testing"
-
-	"gopkg.in/yaml.v2"
 )
 
 func cmdOutput(t *testing.T, args []string) string {
@@ -46,10 +44,14 @@ func TestShow(t *testing.T) {
 			err = json.Unmarshal([]byte(text), &ret)
 			return
 		},
+
+		/* Temporarily(!) disabled due to
+		   https://github.com/ksonnet/kubecfg/issues/99
 		"yaml": func(text string) (ret interface{}, err error) {
 			err = yaml.Unmarshal([]byte(text), &ret)
 			return
 		},
+		*/
 	}
 
 	// Use the fact that JSON is also valid YAML ..