filter-doc-snarfage.c: new files.
* Makefile.am: add stuff to [build,] use and distribute
guile-snarf-docs, guile-snarf-docs-texi, guile_filter_doc_snarfage.
* guile-snarf.in: grok the new snarf output.
* snarf.h: make the output both texttools- and `read'-friendly.
* guile-doc-snarf.in (bindir): reimplement in terms of guile-snarf
and guile-snarf-docs. (should also deprecate, I guess. maybe
not).
