Allow configuring the encryption handlers

[tonysm]

Changed

• Allows configuring the encryption handles. By default, Laravel's encryption will serialize the value before encrypting. But the preferred way is actually to encrypt it as a string. For BC reasons, I'll introduce this new way of configuring the encryption with a new method to enable storing the encryption as string if you want to. In 2.x, this will be opt-in, but I'll tag 3.x because I want this to be the default way. I'll add some notes on how to migrate the currently encrypted data for folks using this feature in 2.x

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issue #51