Remove special case for exchange require

lib/trader.js

@@ -25,19 +25,7 @@ var Trader = module.exports = function (db) {
 };
 
 Trader.prototype._findExchange = function (name) {
-  var exchange;
+  return require('lamassu-' + name);
-
-  try {
-    exchange = require('lamassu-' + name);
-  } catch (err) {
-    if (!err.message.match(/Cannot find module/)) {
-      throw err;
-    }
-
-    exchange = require(path.join(path.dirname(__dirname), 'exchanges', name));
-  }
-
-  return exchange;
 };
 
 Trader.prototype._findTicker = function (name) {