On cydia's home page you will see Manage Account.
Login to your account with Facebook or Google
Once logged in you will see installable purchased. Tap it.
Tap Link Device to Your Account
That's it since you previously purchased iFile it will let you download. This will also allow you to download other purchases you have made, but be careful as most are not updated to iOS8.
You can use iFile to install files that you download. Here is a tutorial on how to install files downloaded from safari. Download and install files with iFile
If you have any questions my Twitter is @JunesiPhone
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