Increased file size limits

To  celebrate the deployment of pixeldrain's new storage system I have raised the file size limit from 10 GB to 20 GB for free users and from 20 GB to 50 GB for Pro subscribers. I have also raised file expiry from 30 days to  60 days!

The free download limit has been updated from 10 GB per day to 20 GB per week in order to accommodate the larger file sizes.