Add hardware crypto capabilities to keystore. This allows hardware
escrow of private key material.
There is also an OpenSSL engine that connects to keystore to allow use
of the keystore keys from native code built into the platform.
This includes a software implementation of keymaster using OpenSSL
as the backend. This is just as insecure as the previous solution,
but it's needed so devices without hardware support can continue
to operate in the new scheme without a lot of compatibility code.
Change-Id: I2bc67766e1f633ef1cbbd2874a65962074e84f4f
Add a libkeystore_client.so library for clients to use.
Add const-correctness to the keystore.cpp classes.
Increase maximum arguments for future work.
Change-Id: Ia22f8b893aea3115a7b4a0543ad392c17c8528f2
