Same Name Sibling created for nt:file type node

When running ModeShape with Fedora 4 in the web environment, we get reported that SN-Sibling files will be created if a large file is submitted twice or more. And when trying to replace the SNS file, a javax.jcr.nodetype.ConstraintViolationException will be thrown with an error message like:

javax.jcr.nodetype.ConstraintViolationException: Cannot find a definition for a child named '{}bar' on the node at '/tests/test-1' with primary type 'nt:folder' and mixin types.

We found that ModeShape will create SNS binary files for a nt:file type node in the multi-user or multi-session environment when two or more files are uploading concurrently with the same file name.

Attached sns_file_test.patch is the patch against the current master branch (5.2-SNAPSHOT) that includes a test to demonstrate the SNS issue we ran into.