Add redirect to handle improper fsnotify rename.

For details see:

https://github.com/go-fsnotify/fsnotify/issues/1

main.go

@@ -157,6 +157,16 @@ func (repo *Repo) SetVersions(all []Version) {
 	}
 }
 
+type repoBase struct {
+	user string
+	name string
+}
+
+var redirect = map[repoBase]repoBase{
+	// https://github.com/go-fsnotify/fsnotify/issues/1
+	{"", "fsnotify"}: {"fsnotify", "fsnotify"},
+}
+
 // GitHubRoot returns the repository root at GitHub, without a schema.
 func (repo *Repo) GitHubRoot() string {
 	if repo.User == "" {
@@ -249,6 +259,10 @@ func handler(resp http.ResponseWriter, req *http.Request) {
 		FullVersion: InvalidVersion,
 	}
 
+	if r, ok := redirect[repoBase{repo.User, repo.Name}]; ok {
+		repo.User, repo.Name = r.user, r.name
+	}
+
 	var ok bool
 	repo.MajorVersion, ok = parseVersion(m[3])
 	if !ok {