Some documentation updates

README.md

@@ -133,5 +133,6 @@ Example programs can be found in the `github.com/miekg/exdns` repository.
 * Last remaining RRs: APL, ATMA, A6 and NXT;
 * Missing in parsing: ISDN, UNSPEC, ATMA;
 * CAA parsing is broken;
+* NSEC(3) cover/match/closest enclose;
 * Replies with TC bit are not parsed to the end.
 * SIG(0)

server.go

@@ -315,8 +315,8 @@ func (srv *Server) ActivateAndServe() error {
 
 // Shutdown gracefully shuts down a server. After a call to Shutdown, ListenAndServe and
 // ActivateAndServe will return. All in progress queries are completed before the server
-// is taken down. If the Shutdown was not succesful an error is taking longer than reading
-// timeout.
+// is taken down. If the Shutdown is taking longer than the reading timeout and error
+// is returned.
 func (srv *Server) Shutdown() error {
 	srv.lock.Lock()
 	if !srv.started {