* src/fileio.c (file_name_case_insensitive_p)
(Ffile_name_case_insensitive_p): New functions.
(Frename_file): Allow renames that simply change case when the
FILE argument is on a case-insensitive filesystem. (Bug#24441)
* lisp/dired-aux.el (dired-do-create-files): Use
'file-name-case-insensitive-p' instead of 'system-type' to check
for case-insensitivity. (Bug#24441)