Fixed Strict Standard Errors

Fixed an issue when with Strict standard Errors when trying to activate Beta Tester plugin under WP3.6. Screenshot attached:

![screen shot 2013-08-11 at 8 54 34 am](https://f.cloud.github.com/assets/1505631/943597/dfa1cbcc-0236-11e3-80ef-9acae26b8cda.png)