Remove mostly all references to APACHE and CGI_BINARY from the code.

- Apache include files are no longer included by any PHP code, except for the Apache SAPI module.
- No server specific code is in any of the base PHP code.

Still left to be done:
- Eliminate any references to APACHE from the few remaining modules.
- Move request_info.c's logic to SAPI
- Modify the regex function names, and globals, so that we can always
  include them, without having to fear any interference with Apache;
  Always use the bundled regex library