fixed write pooling release. This makes writes work for master/slave MySQL setups

lib/dialects/mysql/connector-manager.js

@@ -108,7 +108,7 @@ module.exports = (function() {
           create: function (done) {
             connect.call(self, function (err, connection) {
               if (connection) {
-                connection.queryType = 'read'
+                connection.queryType = 'write'
               }
 
               done(err, connection)
@@ -153,7 +153,7 @@ module.exports = (function() {
 
       return
     }.bind(this);
-    
+
     process.on('exit', this.onProcessExit)
   }
 
@@ -185,7 +185,7 @@ module.exports = (function() {
           setTimeout(function() {
             if (self.pendingQueries === 0){
               self.disconnect.call(self);
-            } 
+            }
           }, 100);
         }
       }