Windows: Don't pull in all of resolvconf

Signed-off-by: John Howard <jhoward@microsoft.com>

resolvconf/dns/resolvconf.go

@@ -0,0 +1,16 @@
+package dns
+
+import (
+	"regexp"
+)
+
+const IpLocalhost = `((127\.([0-9]{1,3}.){2}[0-9]{1,3})|(::1))`
+
+var localhostIPRegexp = regexp.MustCompile(IpLocalhost)
+
+// IsLocalhost returns true if ip matches the localhost IP regular expression.
+// Used for determining if nameserver settings are being passed which are
+// localhost addresses
+func IsLocalhost(ip string) bool {
+	return localhostIPRegexp.MatchString(ip)
+}