#265973 by clemens.tolboom, Damien Tournoud, Uccio, dixon_, mr.baileys: make Drupal capable of handling bigger XML-RPC messages by removing some unnecessary processing

#245990 follow up by Damien Tournoud, David_Rothstein, pwolanin: Move back to an internal URL check for HTTP request checking and make the request checking less intrusive on what requests can be accomplished

#208270 reported by Dries, patch by jvandyk: it was not possible to clear the XML-RPC error cache, making it impossible to do multiple queries in one request. Add xmlrpc_clear_error() and slightly modify xmlrpc_error() to fix.

- Patch #204900 by webernet: code style fixes.  Likely my last patch of the year.  Fiew.  Thanks all, and see you on the other side.  :)

#196535 by sun, chx, dww: check whether Drupal can issue HTTP requests at all, so we know that this is the cause of problems, not the remote host not responding.

 - whitespaces at end of lines
 - indentation
 - control structure usage
 - whitespace in empty lines
 - phpdoc comment formatting

- Patch #137138 by jvandyk: fixed problem with drupal_http_request() not setting the proper error code when a network effect occurs.  Causes the XML-RPC backend to fail.

/me looks down
OH MY GOD... I'M MELLLLTTIIINNGG NOOOOOOO.... AAARGHHHHHH.

Oh well, don't the people inside the asylum say the outside world is insane, too?

   * xmlrpc_value_calculate_type() fails for empty arrays
   * PHPDoc for xmlrpc_value_calculate_type()
   * use is_*() instead of gettype() as advised in the PHP manual (and document this)
   * coding style

- Patch #7458 by chx: merged the XML-RPC multicall support into xmlrpc() and use lazy-loading for the XML-RPC libraries.(performance improvement).

- Patch #28482 by Uwe: add CVS $Id$ tags to all source files in Drupal core. This allows admins to know exactly which version of which files they use. In addition I want to use CVS $Id$ tags in my upcoming security.module to check for possible vulnerabilities. That's not possible if some files simply don't have $Id$s.

Note: I also (mostly) unified the tags to use the "// ID" form instead of "/* ID */", but that's more of a cosmetic issue. I'm not sure whether *.txt files and the stuff in themes/ need tags(?).

- Patch #11728 by Uwe Hermann: fixed some typos in the code comments, Doxygen documentation and screen output.

  Uwe: I dropped the 'iff' chunks as 'iff' stands for 'if and only if'.