Config processing with lazy error handling

[luk-kaminski]

Fixes #126

Notes for Reviewers

• The commit history must be preserved - please use the rebase-merge or standard merge option instead of squash-merge
• Sync up with the author before merging

[todvora]

I have adapted the behaviour to match the eager processing mode. The lazy method now doesn't return any result, the return type is void. The outcome of the processing is either configured beans or a ValidationException, aggregating all the errors and providing access to the underlying ProcessingResponse, if the caller wants to handle the errors in a specific way.

This is how the exception looks now, aggregating three missing properties:

The only change from the caller perspective is to switch from jadConfig.process() to jadConfig.processFailingLazily(). Everything else can stay as it is, with the same error handling in place as before.