Annotation based Serializer and Deserializer

This PR adds support for annotation based serializer encryption and deserializer encryption.  To use this feature, you need to create a CryptoModule and add it to the ObjectMapper.

Registration of the module looks like:

```
EncryptionService service = ...;
ObjectMapper mapper = ...;
mapper.registerModule(new CryptoModule(service));
```

And the annotated properties look like:

```
  @Encrypted
  public String property;
```

This PR is a work in progress.
We need to do something about bootstrapping DropWizard.  At first, you will only have the environment for decryption, and then the key table will be available from the config.  Either we need to be able to get the keys in later, or we need to move the keys into the environment.