Make things sort of work in IE8

Summary:
Uploaded the OTFs from eab3322d to fontsquirrel with the following config:

```
{"mode":"expert","formats":["ttf","woff","eotz"],"tt_instructor":"default","fix_vertical_metrics":"Y","fix_gasp":"xy","add_spaces":"Y","add_hyphens":"Y","fallback":"none","fallback_custom":"100","options_subset":"none","subset_custom":"","subset_custom_range":"","css_stylesheet":"stylesheet.css","filename_suffix":"","emsquare":"2048","spacing_adjustment":"0"}
```

Now we have this beauty in IE8:

{F213}

and it looks similar in Chrome. Now I guess we just need square roots so we can stop disseminating the wrong quadratic formula.

Reviewers: xymostech

Reviewed By: xymostech

Differential Revision: http://phabricator.benalpert.com/D43

static/main.js

@@ -2,9 +2,15 @@ window.onload = function() {
     var input = document.getElementById("input");
     var math = document.getElementById("math");
 
-    MJLite.process(input.value, math);
+    reprocess();
 
-    input.oninput = function() {
+    if ("oninput" in input) {
+        input.addEventListener("input", reprocess, false);
+    } else {
+        input.attachEvent("onkeyup", reprocess);
+    }
+
+    function reprocess() {
         MJLite.process(input.value, math);
-    };
+    }
 };