The JNIKiwixManager is used to manage (insertion of book in) the library.
It is created, as needed, using an existing Library as input.
It is then used to add books, parse library.xml or opds content.
Then it can be destruct (and must be) with the `dispose` method.
```java
library = JNILibrary(...);
manager = JNIManager(library);
manager.parseOpds(opdscontent);
manager.dispose();
// library contains the books declared in the opds content.
// Use the library methods to get the books' info.
```
Matthieu Gautier