Typo in exception message

There is simple typo error in org.infinispan.loaders.file.FileCacheStore on line 461.

"isDirector" should be "isDirectory"

Here is example of thrown exception:

IO error occurred when listing files with filter org.infinispan.loaders.file.FileCacheStore$NumericNamedFilesFilter@2773a64a [fileExists=false, isDirector=false, canRead=false, canWrite=false]