Speed up make_paragraphs.

Speed up make_paragraphs.
* automake.in (handle_languages): Always define SUBDIROBJ,
DERIVED-EXT, and DIST_SOURCE, because the new transform() will
abort on unknown tokens.
(transform): Rewrite with different semantics.
(make_paragraphs): Make a single pass over the paragraph to
transform all template tokens instead of doing as much passes as
possible token.