Fix hook sorting for the pre_config hook. Move modules/http/config2.m4 back to modules/http/config.m4, since this was only done as work-around in r88887 for the broken hook-sorting.

Move the keepalives field out of the conn_rec and into an HTTP specific connection record. This also moves some HTTP specific back out of the core and into the HTTP module.

Move more code from the http module into the core server. This is core code, basically the default handler, the default input and output filters, and all of the core configuration directives. All of this code is required in order for the server to work, with or without HTTP. The server is closer to working without the HTTP module, although there is still more to do. I tried to fix Windows, but somebody should probably make sure I did it correctly.

Move the error_bucket definition from the HTTP module to the core server. Every protocol will need this definition, so it belongs in the core.

filters can now report an HTTP error to the server. This is done by sending a brigade where the first bucket is an error_bucket. This bucket is a simple bucket that stores an HTTP error and a string. Currently the string is not used, but it may be needed to output an error log. The http_header_filter will find this bucket, and output the error text, and then return AP_FILTER_ERROR, which informs the server that the error web page has already been sent.

Add a couple of files that I missed earlier today.