fix: don't create empty clientError listener for http.Server (#1895)

Author: nigelis

lib/server.js

@@ -142,7 +142,6 @@ function Server(options) {
     this.acceptable = fmt.acceptable;
     this.formatters = fmt.formatters;
     this.proxyEvents = [
-        'clientError',
         'close',
         'connection',
         'error',

test/server.test.js

@@ -2514,13 +2514,13 @@ test('should have proxy event handlers as instance', function(t) {
     var server = restify.createServer({
         handleUpgrades: false
     });
-    t.equal(server.proxyEvents.length, 7);
+    t.equal(server.proxyEvents.length, 6);
 
     server = restify.createServer({
         handleUpgrades: true
     });
 
-    t.equal(server.proxyEvents.length, 6);
+    t.equal(server.proxyEvents.length, 5);
     server.close(function() {
         t.end();
     });