Add route capabilities to hibernate module.

Adds database routing ability (via 'RouteKey' HTTP header) for Hibernate.

In Configuration Class:
```java
@Valid
@NotNull
private ImmutableList<DataSourceRoute> databases;
```

In yaml file:
```yaml
# Database settings.
databases:
  - routeName: routeone
    database:
      # the name of your JDBC driver
      driverClass: com.mysql.jdbc.Driver

      # the username
      user: userone

      # the password
      password: password

      # the database url
      url: jdbc:mysql://hostone.com:3306/myapp
  - routeName: routetwo
    database:
      # the name of your JDBC driver
      driverClass: com.mysql.jdbc.Driver

      # the username
      user: usertwo

      # the password
      password: password

      # the database url
      url: jdbc:mysql://hosttwo.com:3306/myapp
```