added methods and routes for getting an exercises history, and the sum of a workouts musclearrays -- incl a modifier

app.js

@@ -8,7 +8,6 @@ http = require('http');
 routes = require('./routes');
 var async = require('async');
 var app = express();
-
 var dbURL = 'mongodb://localhost/database';
 var db = require('mongoose').connect(dbURL);
 var qs = require('qs');