Updates spf13/cobra dep to v0.0.5

 Fixes knative#426

 - and a couple of patches on top which aren't merged yet
 	- spf13/cobra#884
	- spf13/cobra#899
 - also updates viper to 1.4.0

go.mod

@@ -1,40 +1,29 @@
 module knative.dev/client
 
 require (
-	github.com/BurntSushi/toml v0.3.1 // indirect
-	github.com/cpuguy83/go-md2man v1.0.10 // indirect
 	github.com/evanphx/json-patch v4.5.0+incompatible // indirect
-	github.com/ghodss/yaml v1.0.0 // indirect
-	github.com/gogo/protobuf v1.2.1 // indirect
-	github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b // indirect
 	github.com/golang/groupcache v0.0.0-20191002201903-404acd9df4cc // indirect
 	github.com/golang/protobuf v1.3.2 // indirect
-	github.com/google/btree v1.0.0 // indirect
 	github.com/google/go-cmp v0.3.1 // indirect
 	github.com/google/go-containerregistry v0.0.0-20190723205234-74f764b9c575 // indirect
 	github.com/googleapis/gnostic v0.3.0 // indirect
 	github.com/gregjones/httpcache v0.0.0-20190611155906-901d90724c79 // indirect
 	github.com/hashicorp/golang-lru v0.5.3 // indirect
 	github.com/imdario/mergo v0.3.7 // indirect
-	github.com/inconshreveable/mousetrap v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.7 // indirect
-	github.com/kr/pretty v0.1.0 // indirect
 	github.com/mattbaird/jsonpatch v0.0.0-20171005235357-81af80346b1a // indirect
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
 	github.com/pkg/errors v0.8.1
-	github.com/spf13/cobra v0.0.3
+	github.com/spf13/cobra v0.0.5
 	github.com/spf13/pflag v1.0.3
-	github.com/spf13/viper v1.3.1
+	github.com/spf13/viper v1.4.0
 	github.com/stretchr/testify v1.4.0 // indirect
-	go.uber.org/atomic v1.4.0 // indirect
 	go.uber.org/multierr v1.2.0 // indirect
-	go.uber.org/zap v1.10.0 // indirect
 	golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2
 	golang.org/x/net v0.0.0-20190724013045-ca1201d0de80 // indirect
 	golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45 // indirect
-	golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 // indirect
 	gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v2 v2.2.4 // indirect
@@ -49,3 +38,5 @@ require (
 	knative.dev/test-infra v0.0.0-20190730202142-17f2331e80ad
 	sigs.k8s.io/yaml v1.1.0
 )
+
+replace github.com/spf13/cobra => github.com/chmouel/cobra v0.0.0-20191021105835-a78788917390