added tooltipElement option to tooltip config. Attempted fix for mult…

…iple instances with multiple tooltips (issues/130)

examples/test/test-tooltips.html

@@ -30,7 +30,7 @@ <h1>Test multiple instances / tooltips</h1>
             <div id="map2" style="height: 300px; width: 50%"></div>
         </div>
 
-        <script src="../../../dist/gridviz.js"></script>
+        <script src="../../dist/gridviz.js"></script>
         <script src="https://cdn.jsdelivr.net/npm/[email protected]"></script>
         <script src="https://cdn.jsdelivr.net/npm/d3-color@3"></script>
         <script src="https://cdn.jsdelivr.net/npm/d3-interpolate@3"></script>