@ Added the ability for CURLOPT_POSTFIELDS to accept an array of HTTP post

@ Added the ability for CURLOPT_POSTFIELDS to accept an array of HTTP post
parameters. (Sterling)
@ Added the CURLOPT_HTTPHEADER option that allows for the posting of HTTP
headers to a remote site from cURL. (Sterling)
@ Add the curl_error() and curl_errno() functions. (Sterling)

Buncha other changes...

  - Changed if () else if () in curl_setopt to switch .. case
  - Fixed a couple crashes in certain cases.
  - Finally a decent error reporting scheme.
  - A few formatting changes.