Revert "Use virtual file based resource manager to make sure deployment overlays work correctly with Undertow"

This reverts commit bd7fa6ed03188a74c89663826d7e6b77df64d8df.

This caused problems JSP, as getResource() on a jar would return the mounted directory, rather than the jar file.
Merge pull request #5562 from stuartwdouglas/undertow

Revert "Use virtual file based resource manager to make sure deployment ...