fixing lint comments

Signed-off-by: David Lawrence <david.lawrence@docker.com> (github: endophage)

signer/signer_trust.go

@@ -133,6 +133,8 @@ func (trust *NotarySigner) CheckHealth(timeout time.Duration) error {
 	return err
 }
 
+// ImportRootKey satisfies the CryptoService interface. It should not be implemented
+// for a NotarySigner.
 func (trust *NotarySigner) ImportRootKey(r io.Reader) error {
 	return errors.New("Importing a root key to NotarySigner is not supported")
 }

tuf/signed/ed25519.go

@@ -119,6 +119,7 @@ func (e *Ed25519) GetPrivateKey(keyID string) (data.PrivateKey, string, error) {
 	return e.keys[keyID].privKey, "", nil
 }
 
+// ImportRootKey adds an Ed25519 key to the store as a root key
 func (e *Ed25519) ImportRootKey(r io.Reader) error {
 	raw, err := ioutil.ReadAll(r)
 	if err != nil {