all: change "true iff" to "whether" in public docs

For consistency with Go documentation style.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/11697043

src/pkg/crypto/ecdsa/ecdsa.go

@@ -124,7 +124,7 @@ func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err err
 }
 
 // Verify verifies the signature in r, s of hash using the public key, pub. It
-// returns true iff the signature is valid.
+// returns whether the signature is valid.
 func Verify(pub *PublicKey, hash []byte, r, s *big.Int) bool {
 	// See [NSA] 3.4.2
 	c := pub.Curve

src/pkg/crypto/x509/pkix/pkix.go

@@ -144,7 +144,7 @@ type CertificateList struct {
 	SignatureValue     asn1.BitString
 }
 
-// HasExpired returns true iff now is past the expiry time of certList.
+// HasExpired returns whether now is past the expiry time of certList.
 func (certList *CertificateList) HasExpired(now time.Time) bool {
 	return now.After(certList.TBSCertList.NextUpdate)
 }

src/pkg/encoding/asn1/asn1.go

@@ -183,7 +183,7 @@ func parseBitString(bytes []byte) (ret BitString, err error) {
 // An ObjectIdentifier represents an ASN.1 OBJECT IDENTIFIER.
 type ObjectIdentifier []int
 
-// Equal returns true iff oi and other represent the same identifier.
+// Equal returns whether oi and other represent the same identifier.
 func (oi ObjectIdentifier) Equal(other ObjectIdentifier) bool {
 	if len(oi) != len(other) {
 		return false