Initial pass at refactoring some files to eliminate our 150K C source behemoths.

      * Makefile.in: Change order of dependencies to bring in exports.o first so that
  we have every symbol 'used' before the linker starts processing.
* build/rules.mk.in: Add a 'program-install' target which just copies httpd.

* server/Makefile.in, modules/http/config2.m4: Add in new file targets.

* NWGNUmakefile, libhttpd.dsp: Blind updates for Netware and Win32.  (I tried.)

* server/core.c: Move core_input_filter, net_time_filter, and core_output_filter  and all supporting functions to...
* server/core_filters.c (copied): ...here.

* modules/http/http_protocol.c: Move functions from here to there...namely:
* modules/http/byterange_filter.c (copied): Relocate ap_byterange_filter() and
  friends.
* modules/http/chunk_filter.c (copied): Relocate chunk_filter().
* modules/http/http_etag.c (copied): Relocate ap_set_etag and ap_make_etag().
* modules/http/http_filters.c (copied): Relocate ap_http_filter(),
  a