Webpack all the things! Fixes #2135

This significantly speeds up loading of the application; in an average of 3 tests, v1.6
loaded in 11.5s in the runtime on a Mac, whilst the webpacked version of the code
loaded in 5.53s.

web/pgadmin/tools/templates/js/translations.js

@@ -1,4 +1,4 @@
 define(function () {
   var translations = {{ translations|tojson }};
-  return translations;
+  return [];
 });