Layout and Advanced Data Grid Examples: Add similar example links

For issues #105 and #155, modified:
* examples/grid/LayoutGrids.html
* examples/grid/advancedDataGrid.html

Add links to the other example pages to the intro.

examples/grid/LayoutGrids.html

@@ -42,6 +42,11 @@ <h1>Layout Grid Examples</h1>
     Thus, a link contained inside of a grid cell is presented to a screen reader as a link.
     By contrast, a link inside of a menu is presented as a menuitem, and a link inside of a listbox is presented as an option.
   </p>
+  <p Similar examples include:</p>
+  <ul>
+    <li><a href="dataGrids.html">Data Grid Examples</a>: Three example implementations of grid that include features relevant to presenting tabular information, such as content editing, sort, and column hiding.</li>
+    <li><a href="advancedDataGrid.html">Advanced Data Grid Example</a>: Example of a grid with behaviors and features similar to a typical spreadsheet, including cell and row selection.</li>
+  </ul>
   <section>
     <h2>Examples</h2>
     <section>

examples/grid/advancedDataGrid.html

@@ -34,6 +34,11 @@ <h1>Advanced Data Grid</h1>
     <a href="../../#grid">design pattern for grid</a>
     demonstrates how to implement a grid that has functionality similar to a spreadsheet.
   </p>
+  <p>Similar examples include:</p>
+  <ul>
+    <li><a href="dataGrids.html">Data Grid Examples</a>: Three example implementations of grid that include features relevant to presenting tabular information, such as content editing, sort, and column hiding.</li>
+    <li><a href="LayoutGrids.html">Layout Grid Examples</a>: Three example implementations of grids that are used to lay out widgets, including a collection of navigation links, a message recipients list, and a set of search results.</li>
+  </ul>
   <section>
     <h2 id="ex_label">Example</h2>
     <div role="separator" id="ex_start_sep" aria-labelledby="ex_start_sep ex_label" aria-label="Start of"></div>