allow for trapping postgres connection errors

connect() returns an event emitter which can be used to handle errors
gracefully rather than throwing an error in callback which would
terminate the entire node process

lib/dialects/postgres/connector-manager.js

@@ -46,6 +46,7 @@ module.exports = (function() {
 
 
   ConnectorManager.prototype.connect = function() {
   ConnectorManager.prototype.connect = function() {
     var self = this
     var self = this
+    var emitter = new (require('events').EventEmitter)()
 
 
     // in case database is slow to connect, prevent orphaning the client
     // in case database is slow to connect, prevent orphaning the client
     if (this.isConnecting) return
     if (this.isConnecting) return
@@ -58,7 +59,7 @@ module.exports = (function() {
       self.isConnecting = false
       self.isConnecting = false
 
 
       if (!!err) {
       if (!!err) {
-        throw err
+        emitter.emit('error', err)
       } else if (client) {
       } else if (client) {
         client.query("SET TIME ZONE 'UTC'")
         client.query("SET TIME ZONE 'UTC'")
           .on('end', function() {
           .on('end', function() {
@@ -78,6 +79,8 @@ module.exports = (function() {
       this.client = new this.pg.Client(uri)
       this.client = new this.pg.Client(uri)
       this.client.connect(connectCallback)
       this.client.connect(connectCallback)
     }
     }
+
+    return emitter
   }
   }
 
 
   ConnectorManager.prototype.disconnect = function() {
   ConnectorManager.prototype.disconnect = function() {