Update deps for Go 1.11

vendor/github.com/miekg/dns/duplicate.go

@@ -0,0 +1,25 @@
+package dns
+
+//go:generate go run duplicate_generate.go
+
+// IsDuplicate checks of r1 and r2 are duplicates of each other, excluding the TTL.
+// So this means the header data is equal *and* the RDATA is the same. Return true
+// is so, otherwise false.
+// It's is a protocol violation to have identical RRs in a message.
+func IsDuplicate(r1, r2 RR) bool {
+	if r1.Header().Class != r2.Header().Class {
+		return false
+	}
+	if r1.Header().Rrtype != r2.Header().Rrtype {
+		return false
+	}
+	if !isDulicateName(r1.Header().Name, r2.Header().Name) {
+		return false
+	}
+	// ignore TTL
+
+	return isDuplicateRdata(r1, r2)
+}
+
+// isDulicateName checks if the domain names s1 and s2 are equal.
+func isDulicateName(s1, s2 string) bool { return equal(s1, s2) }