Update encryption commands.

* Changed to inplace encryption.
* Changed decryption to return the proper error code. It will now return success or the number of failed attempts.
* Be lazy and post a message 2 seconds later to call restart. I don't feel like messing with binder interfaces for a proper callback.

Change-Id: Iae2de7057aa66f248fd2df3f29777ad3368442f0