Add warning for validations in schema.js

lib/railway.js

@@ -43,6 +43,21 @@ railway.orm._schemas.forEach(function (schema) {
     schema.freeze();
 });
 
+// check validations and display warning
+
+var displayWarning = false;
+Object.keys(app.models).forEach(function (model) {
+    var Model = app.models[model];
+    if (Model._validations) {
+        displayWarning = true;
+    }
+});
+
+if (displayWarning) {
+    var $ = railway.utils.stylize.$;
+    require('util').puts($('WARNING:').bold.red + ' ' + $('I can see that you\'ve added validation to db/schema.js. However schema.js file is only used to describe database schema. Therefore validations configured in db/schema.js will be ignored.\nFor business logic (incl. validations) please create models as separate .js files here: app/models/*.js').yellow);
+}
+
 function log(str, startTime) {
     var $ = railway.utils.stylize.$;
     var m = Date.now() - startTime;