Added caching of last 30 day stats

Efficiency Results:
Original uncached load times for index.php
12,498 ms
12,480 ms
12,546 ms
12,492 ms
12,488 ms
Avg = 12,500.8 ms

Cached load times for index.php
7,768 ms
7,786 ms
7,766 ms
7,960 ms
7,772 ms
Avg = 7,810.4 ms