fix typo in index.html

index.html

@@ -3234,7 +3234,7 @@ <h2 id="faq">F.A.Q.</h2>
       ... in your configuration. Otherwise, override
       <a href="#Model-parse">parse</a> to pull model attributes out of the
       wrapper. Similarly, Backbone PUTs and POSTs direct JSON representations
-      of models, where by default Rails expcects namespaced attributes. You can
+      of models, where by default Rails expects namespaced attributes. You can
       have your controllers filter attributes directly from <tt>params</tt>, or
       you can override <a href="#Model-toJSON">toJSON</a> in Backbone to add
       the extra wrapping Rails expects.