Fix example 8's attribute usage. Thanks to @TommySorensen

- field-required had some string not "true"

example/index.html

@@ -283,7 +283,7 @@ <h3><a name="example7" class="page-anchor">Example 7 - Callback</a></h3>
       minlength="1"
       input-class="form-control form-control-small"
       match-class="highlight"
-      field-required="requireExample8a"
+      field-required="true"
       input-name="country8a"&gt;
     &lt;/div&gt;
 
@@ -298,7 +298,7 @@ <h3><a name="example7" class="page-anchor">Example 7 - Callback</a></h3>
       minlength="1"
       input-class="form-control form-control-small"
       match-class="highlight"
-      field-required="requireExample8b"
+      field-required="true"
       input-name="country8b"&gt;
     &lt;/div&gt;
   &lt;/div&gt;
@@ -308,10 +308,10 @@ <h3><a name="example7" class="page-anchor">Example 7 - Callback</a></h3>
           <h3><a name="example8" class="page-anchor">Example 8 - Required</a><span ng-show="form.$valid" class="valid-status valid">[VALID]</span><span class="valid-status invalid" ng-show="form.$invalid">[INVALID]</span></h3>
           <div class="padded-row">
             <span>Choose two countries</span>
-            <div angucomplete-alt id="ex8a" placeholder="Search countries" pause="100" selected-object="countrySelected8a" local-data="countries" search-fields="name" title-field="name" minlength="1" input-class="form-control form-control-small" match-class="highlight" field-required="requireExample8a" input-name="country8a">
+            <div angucomplete-alt id="ex8a" placeholder="Search countries" pause="100" selected-object="countrySelected8a" local-data="countries" search-fields="name" title-field="name" minlength="1" input-class="form-control form-control-small" match-class="highlight" field-required="true" input-name="country8a">
             </div>
 
-            <div angucomplete-alt id="ex8b" placeholder="Search countries" pause="100" selected-object="countrySelected8b" local-data="countries" search-fields="name" title-field="name" minlength="1" input-class="form-control form-control-small" match-class="highlight" field-required="requireExample8b" input-name="country8b">
+            <div angucomplete-alt id="ex8b" placeholder="Search countries" pause="100" selected-object="countrySelected8b" local-data="countries" search-fields="name" title-field="name" minlength="1" input-class="form-control form-control-small" match-class="highlight" field-required="true" input-name="country8b">
             </div>
           </div>
         </form>