Fix broken links

Issue #742

tutorials/code.md

@@ -67,7 +67,7 @@ To make sure everything works, we are going to add a sphere, set the camera, ren
 </script>
 ```
 
-Documentation: [$3Dmol.createViewer()]($3Dmol.html#createViewer)
+Documentation: [$3Dmol.createViewer()](global.html#createViewer)
 
 <div class="align-center">
   <button id="btn-01" class="btn btn-primary">Try it</button>
@@ -96,7 +96,7 @@ jQuery(function() {
 
 If this has worked, you should see a rather fetching green ball in front of an orange background. If not, then now's a good time to get familiar with the developer console on your favourite browser and check for typos ([Firefox](https://developer.mozilla.org/en/docs/Tools/Web_Console), [Chrome](https://developers.google.com/web/tools/chrome-devtools/), ...)
 
-Note, the ```viewer``` variable now contains an instance of GLViewer and we use the [$3Dmol.GLViewer API]($3Dmol.GLViewer) to change the orange background white.
+Note, the ```viewer``` variable now contains an instance of GLViewer and we use the [$3Dmol.GLViewer API](GLViewer.html) to change the orange background white.
 
 ```
   viewer.setBackgroundColor('white');
@@ -106,7 +106,7 @@ Note, the ```viewer``` variable now contains an instance of GLViewer and we use
   <button id="btn-01-alt" class="btn btn-primary">Try it</button>
 </div>
 
-Documentation: [$3Dmol.GLViewer API]($3Dmol.GLViewer)
+Documentation: [$3Dmol.GLViewer API](GLViewer.html)
 
 ### Loading data dynamically