title: kendo grid filter works with "contains" but not equality
body: <p>I can't get the equality filter ("is equal to" or "is not equal to") to work on the "Request Status" column in a kendo grid.  I can use it on other columns in the grid, such as Buyer.</p>
  
  <p>But the "contains" filter works on the "Request Status" column.  Why doesn't equals work?</p>
  
  <p>Example:  Contains "Rejected" filters correctly.  Equal to "Rejected" does not.</p>
  
  <p><strong>HTML:</strong></p>
  
  <pre><code>&lt;div class="k-content"&gt;
      &lt;table id="grid" style="display:none;"&gt;
          &lt;colgroup&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
              &lt;col /&gt;
          &lt;/colgroup&gt;
          &lt;thead style="font-size:80%;"&gt;
              &lt;tr&gt;
                  &lt;th&gt;Id&lt;/th&gt;
                  &lt;th&gt;Request Status&lt;/th&gt; 
                  &lt;th&gt;Vendor Rep&lt;/th&gt;
                  &lt;th&gt;Buyer&lt;/th&gt;
                  &lt;th&gt;UPC&lt;/th&gt;
                  &lt;th&gt;Brand&lt;/th&gt;
                  &lt;th&gt;Description&lt;/th&gt;
                  &lt;th&gt;Create Date&lt;/th&gt;
                  &lt;th&gt;Update Date&lt;/th&gt;
              &lt;/tr&gt;
          &lt;/thead&gt;
          &lt;tbody&gt;
              @foreach (var itemRequest in this.Model)
              {
                  &lt;tr&gt;
                      &lt;td&gt;@itemRequest.Id&lt;/td&gt;
                      &lt;td&gt;@(itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.Draft ? "Draft" :
                              (itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.MerchandisingReview ? "Merchandising" :
                              (itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.SpacePlanningReview ? "Space Planning" :
                              (itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.DataIntegrityReview ||
                                  itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.DataIntegrityFinalReview ? "Data Integrity" :
                              (itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.VendorRepReview ? "Vendor Rep" :
                              (itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.Approved ? "Approved" :
                              (itemRequest.ItemRequestStatusId == Portal.BusinessModel.Entities.ItemRequestStatusId.Rejected ? "Rejected" : ""
                              )))))))
                       &lt;/td&gt;
                      &lt;td&gt;@itemRequest.GetAuthor().FirstName @itemRequest.GetAuthor().LastName&lt;/td&gt;
                      &lt;td&gt;@(itemRequest.GetBuyer() != null ? @String.Format("{0}", itemRequest.GetBuyer().Name) : "")&lt;/td&gt;                    
                      &lt;td&gt;@itemRequest.Upc&lt;/td&gt;
                      &lt;td&gt;@itemRequest.BrandCode&lt;/td&gt;
                      &lt;td&gt;@itemRequest.Description&lt;/td&gt;
                      &lt;td&gt;@itemRequest.CreateDate.ToShortDateString()&lt;/td&gt;
                      &lt;td&gt;@(itemRequest.LastUpdateDate.HasValue ? ((DateTime)itemRequest.LastUpdateDate).ToShortDateString() : "")&lt;/td&gt;
                  &lt;/tr&gt;
              }
          &lt;/tbody&gt;
      &lt;/table&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p><strong>Script:</strong></p>
  
  <pre><code>&lt;script src="~/Content/Scripts/kendo/js/kendo.web.js"&gt;&lt;/script&gt;
      &lt;script type="text/javascript"&gt;
          $(document).ready(function () {
              $("#grid").kendoGrid({
                  sortable: true,
                  scrollable: false,
                  filterable: true,
                  pageable: true,
                  dataSource: {
                      schema: {
                          model: {
                              id: "Id",
                              fields: {
                                  Id: { type: "number" },
                                  //2014-03-27: Issue #69
                                  ItemRequestStatusId: { type: "string" },
                                  VendorRep: { type: "string" },
                                  Buyer: { type: "string" },
                                  Upc: { type: "number" },
                                  Brand: { type: "string" },
                                  Description: { type: "string" },
                                  CreateDate: { type: "date" },
                                  UpdateDate: { type: "date" }
                              }
                          }
                      },
                      pageSize: 10
                  },
                  columns: [
                      { field: "Id", template: "&lt;a href=\"/items/itemrequest/display/#: Id #\"&gt;#: Id # &lt;/a&gt;" },
                      { field: "ItemRequestStatusId" },
                      { field: "VendorRep" },
                      { field: "Buyer" },
                      { field: "Upc" },
                      { field: "Brand" },
                      { field: "Description" },
                      { field: "CreateDate", format: "{0:MM/dd/yyyy}" },
                      { field: "UpdateDate", format: "{0:MM/dd/yyyy}" }
                  ]
              });
  
              $("#grid").css("display", "table");
  
              var grid = $("#grid").data("kendoGrid");
              var hide = $('#hide_Status').val()
              if(hide)
              {
                  grid.hideColumn(1);
              }
  
              var tacos = 0;
          });
      &lt;/script&gt;
  </code></pre>