Enable an optional username:password to be provide on the command line to generate a Basic authentication header.
Enable an optional username:password to be provide on the command line to
generate a Basic authentication header.

* test/serf_get.c:
  (main): look for a third param, base64-encode it, and pass it in the
    "Authorization:" header.


git-svn-id: 683495cb1553624b05a54e2ba9533425f69cf277@233 61a7d7f5-40b7-0310-9c16-bb0ea8cb1845

coapp-packages/serf,coapp-packages/serf,coapp-packages/serf