ed: Don't match against line 0 in search()

regexec(3) happily matches /^$/ against the text of line
zero (the null string), causing an error.

Also update email address for Wolfgang Corcoran-Mathe

LICENSE

@@ -58,6 +58,6 @@ Authors/contributors include:
 © 2015 Tai Chi Minh Ralph Eastwood <tcmreastwood@gmail.com>
 © 2015 Quentin Rameau <quinq@quinq.eu.org>
 © 2015 Dionysis Grigoropoulos <info@erethon.com>
-© 2015 Wolfgang Corcoran-Mathe <first.lord.of.teal@gmail.com>
+© 2015 Wolfgang Corcoran-Mathe <wcm@sigwinch.xyz>
 © 2016 Mattias Andrée <maandree@kth.se>
 © 2016 Eivind Uggedal <eivind@uggedal.com>

ed.c

@@ -426,7 +426,7 @@ search(int way)
 	i = curln;
 	do {
 		i = (way == '?') ? prevln(i) : nextln(i);
-		if (match(i))
+		if (i > 0 && match(i))
 			return i;
 	} while (i != curln);