Move post code chunks to Gists

Also, remove highlight specific things from style.sass

_posts/2013-03-05-haversine-in-mysql.markdown

@@ -14,13 +14,4 @@ Just insert it in your database, feed them two Google coordinates, and you get
 the distance in kilometres. If you happen to need it in miles, change the
 constant `12756.200` in the `RETURN` row to `7922.6` instead.
 
-{% highlight sql %}
-DELIMITER $$
-
-CREATE FUNCTION `haversine` (lng1 FLOAT, lat1 FLOAT, lng2 FLOAT, lat2 FLOAT)
-RETURNS float NO SQL DETERMINISTIC
-BEGIN
-    SET @a = ABS(POWER(SIN(RADIANS(lat1 - lat2)) / 2, 2) + COS(RADIANS(lat1)) * COS(RADIANS(lat2)) * POWER(SIN(RADIANS(lng1 - lng2)) / 2, 2));
-    RETURN 12756.200 * ATAN2(SQRT(@a), SQRT(1 - @a));
-END$$
-{% endhighlight %}
+{% gist gergelypolonkai/bdad1cf2d410853bef35 %}