Update helper.php

Prevents thousands separator (",") from being used when total cache size exceeds 1mb.

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=31826
[#31973] Installation loop if sending config yes (3.2 alpha) (Fix #1992)
[#31963] Incorrect or inconsistent characters in 'close ink' text on alert info popups (Fix #1949)
Merge pull request #1872 from drewgg/patch-2

Update helper.php