Stratify certificate loading and self-sign cert generation

This removes all dependencies on Config during cert generation, only operating
on ServerRunOptions. This way we get rid of the repeated call of Config.Complete
and cleanly stratify the GenericApiServer bootstrapping.

pkg/genericapiserver/options/server_run_options.go

@@ -75,7 +75,6 @@ type ServerRunOptions struct {
 	// for testing). This is not actually exposed as a flag.
 	DefaultStorageVersions string
 	TargetRAMMB            int
-	TLSCAFile              string
 	WatchCacheSizes        []string
 }