docs(input): fix typo

Fix a typo on an example from the `input` directive

src/ng/directive/input.js

@@ -514,7 +514,7 @@ var inputType = {
         }]);
      </script>
      <form name="myForm" ng-controller="DateController as dateCtrl">
-       Pick a month int 2013:
+       Pick a month in 2013:
        <input id="exampleInput" type="month" name="input" ng-model="value"
           placeholder="yyyy-MM" min="2013-01" max="2013-12" required />
        <span class="error" ng-show="myForm.input.$error.required">