This adds code to handle ECC records; the RSA code remains intact.
While old password records are not affected, new records use ECC. Due to
the use of public keys to encrypt a KEK that is then used to encrypt
data, there is no visible change to end users. A user with an RSA key
can interact and share a secret with a user who has an ECC key.
The bulk of this commit simply adds cases for handling EC records.
The passvault's id is created with math.rand as a native int.
If the vault is created on a 64-bit system, it breaks compatibility
with 32-bit systems.
- Generate vaults with 32-bit ids.
- Update testcode
