Add more convenience methods to PersistenceConfiguration

[hantsy]

I found there only provides a managedClass(Class<?> class) method in the PersistenceConfiguration, but does not provides methods to add a collection of classes.

eg.

PersistenceConfiguration managedClasses(Class<?> classes...)
PersistenceConfiguration managedClasses(Collection<Class<?>> classes)

// add all jpa managed classes in the package located by the specified class
PersistenceConfiguration managedPackage(Class<?> class)
PersistenceConfiguration managedPackages(Class<?> classes...) 
PersistenceConfiguration managedPackages(Collection<Class<?>> classes)

[gavinking]

The way I usually do this is:

PersistenceConfiguration config = new PersistenceConfiguration();
...
List.of(Book.class, Author.class, Publisher.class).forEach(config::managedClass);

which seems .... fine, I guess.