data export commit, supports exporting task history via csv

*adds the following new dependencies: moment, express-csv
*recommend replacing functionality of 'relative-date' with features from 'moment'
*supports retrieval of CSV history via the API and in browser
**/api/v1/export/history (requires typical API authorization)
**/export/history.csv (requires session authorization)
*adds new routes for data export

src/server.js

@@ -116,6 +116,7 @@ if ("development" === app.get("env")) {
 app.use(require('./routes/pages').middleware);
 app.use(require('./routes/auth').middleware);
 app.use('/api/v1', require('./routes/api').middleware);
+app.use('/export', require('./routes/dataexport').middleware);
 app.use(require('./controllers/deprecated').middleware);
 server = http.createServer(app).listen(app.get("port"), function() {
   return console.log("Express server listening on port " + app.get("port"));