Support for reporting owner and group of each file on MS-Windows:

Support for reporting owner and group of each file on MS-Windows:
	* dired.c (stat_uname, stat_gname): New functions, with special
	implementation for w32.
	(Ffile_attributes): Use them instead of getpwuid and getgrgid.

	* w32.c:
	(g_b_init_get_file_security, g_b_init_get_security_descriptor_owner)
	(g_b_init_get_security_descriptor_group, g_b_init_is_valid_sid):
	New initialization states.
	(globals_of_w32): Initialize them to zero.  Initialize the default
	group name to "None".
	(GetFileSecurity_Name): New global var, the name of the function
	to call for GetFileSecurity.
	(GetFileSecurity_Proc, GetSecurityDescriptorOwner_Proc)
	(GetSecurityDescriptorGroup_Proc, IsValidSid_Proc): New typedefs.
	(get_file_security, get_security_descriptor_owner)
	(get_security_descriptor_group, is_valid_sid)
	(get_file_security_desc, get_rid, get_name_and_id)
	(get_file_owner_and_group): New functions.
	(stat): Use get_file_security_desc and get_file_owner_and_group to
	report the owner and primary group of each file.  Don't ignore the
	high 32 bits of file's size, now that st_size is 64-bit wide.  Fix
	test when to get true file attributes.
	(init_user_info): Use get_rid instead of equivalent inline code.
	(fstat): Don't ignore the high 32 bits of file's size.