Adds support for instance name based MS SQL connections.

This commit checks if in the passed options for Sequelize a instanceName
dialect option was passed for MS SQL connections. It sets the
instanceName property on the config and omits the port property, so that
tedious will use the instance name instead of a direct port connection.

Signed-off-by: Luca Moser <l.moser@triumph-adler.ch>

lib/dialects/mssql/connection-manager.js

@@ -28,11 +28,15 @@ ConnectionManager.prototype.connect = function(config) {
       server: config.host,
       server: config.host,
       /* domain: 'DOMAIN' */
       /* domain: 'DOMAIN' */
       options: {
       options: {
-        port: config.port,
         database: config.database,
         database: config.database,
       }
       }
     };
     };
 
 
+    // only set port if no instance name was provided
+    if(!config.dialectOptions.instanceName){
+      connectionConfig.options.port = config.port;
+    }
+
     if (config.dialectOptions) {
     if (config.dialectOptions) {
       Object.keys(config.dialectOptions).forEach(function(key) {
       Object.keys(config.dialectOptions).forEach(function(key) {
         connectionConfig.options[key] = config.dialectOptions[key];
         connectionConfig.options[key] = config.dialectOptions[key];