1. update clientset, deepcopy using code-generator

2. add a dummy file tools.go to force "go mod vendor" to see
code-generator as dependencies
3. add a script to update CRD
4. add a README to document CRD updating steps
run go mod tidy
update README

vendor/k8s.io/client-go/tools/cache/OWNERS

@@ -33,8 +33,6 @@ reviewers:
 - madhusudancs
 - hongchaodeng
 - krousey
-- markturansky
-- fgrzadkowski
 - xiang90
 - mml
 - ingvagabund
@@ -42,10 +40,6 @@ reviewers:
 - jessfraz
 - david-mcmahon
 - mfojtik
-- '249043822'
-- lixiaobing10051267
-- ddysher
 - mqliang
-- feihujiang
 - sdminonne
 - ncdc