Add Support for Fully URL-Configured Pools

Fixes #811 (I think)

Author: skeggse

lib/PoolConfig.js

@@ -3,6 +3,10 @@ var ConnectionConfig = require('./ConnectionConfig');
 
 module.exports = PoolConfig;
 function PoolConfig(options) {
+  if (typeof options === 'string') {
+    options = ConnectionConfig.parse(options);
+  }
+
   this.connectionConfig   = new ConnectionConfig(options);
   this.waitForConnections = (options.waitForConnections === undefined)
     ? true