Add support for overriding generic pool defaults

Author: Nuno Sousa

lib/pool.js

@@ -17,10 +17,10 @@ var pools = {
     }
     pool = genericPool.Pool({
       name: name,
-      max: defaults.poolSize,
-      idleTimeoutMillis: defaults.poolIdleTimeout,
-      reapIntervalMillis: defaults.reapIntervalMillis,
-      log: defaults.poolLog,
+      max: clientConfig.poolSize || defaults.poolSize,
+      idleTimeoutMillis: clientConfig.poolIdleTimeout || defaults.poolIdleTimeout,
+      reapIntervalMillis: clientConfig.reapIntervalMillis || defaults.reapIntervalMillis,
+      log: clientConfig.poolLog || defaults.poolLog,
       create: function(cb) {
         var client = new pools.Client(clientConfig);
         client.connect(function(err) {