Disallow storing a Lucene index when storeAsBinary is enabled

As discussed on the mailing list, this configuration doesn't make sense for the Lucene Directory and can cause trouble.
Let's add some validation to throw a runtime exception to disallow this configuration when a Directory is created on a cache.

Could probably be done in a very similar way as:
https://github.com/infinispan/infinispan/commit/2f6447e197abe2e9e62c796ab0f0e8ba524d34be