All C and H files now (should) feature the proper project curl source
code header, which includes basic info, a copyright statement and some
basic disclaimers.
file got a Last-Modified: header written to the data stream, corrupting the
actual data. This was because some conditions from the previous FTP code was
not properly brought into the new FTP code. I fixed and I added test case 520
to verify. (This bug was introduced in 7.13.1)