addresses a few more issues from PR#2474

- adds project header to multiple files
- updates spell check skip words
- removes linux only flags direct,noatime from mac_os build
- applies rustfmt to test_dd

tests/by-util/test_dd.rs

@@ -1,3 +1,5 @@
+// spell-checker:ignore (Fileio fname fpath fullblock gibi ifile iflag infile lcase noatime nocreat notrunc noxfer ofile oflag outfile specfile testfile TESTFILE tname ucase unspec urand)
+
 use crate::common::util::*;
 
 use std::fs::{File, OpenOptions};