DRQS 30903544 bdls_filesystemutil docs update.
DRQS 30903544 bdls_filesystemutil docs update.

bdls_filesystemutil docs should be explicit about behavior re symbolic
links

che2/bde,che2/bde,bloomberg/bde,che2/bde,bloomberg/bde,bloomberg/bde,che2/bde,bloomberg/bde,bloomberg/bde