Need more regression tests with fixed inputs to verify expected outputs

Should have more tests that run hard-coded values through the recrypt algorithms to verify that the expected outputs are produced. For example:

- For a fixed RNG (all zeroes, all ones, or a known sequence of some kind), make sure we get the expected value from GeneratePlaintext
- For a fixed RNG, make sure we get the expected output from GenerateKeyPair
- For a fixed RNG and fixed input, make sure we get the expected TransformKey

Similar checks for encrypt operations and transform operations.