Do not output .lo rules for programs and static libraries objects,

Do not output .lo rules for programs and static libraries objects,
and do not output .o/.obj rules for libtool libraries.  This is
about explicit rules only, not inference rules.
* automake.in (handle_single_transform_list): Rename as ...
(handle_single_transform): ... this.  Take a single file
to transform (it was only called this way) and accept a new
%transform argument.  Fill %lang_specific_files with list
references instead of strings, and append %transform to each
of these lists.
(define_objects_from_sources, handle_source_transform):
Take a %transform argument, and forward it to &handle_single_transform.
(handle_languages): Adjust to the new format of
%lang_specific_files, and honor its %transform part.
(handle_programs, handle_libraries, handle_ltlibraries): Override
%NONLIBTOOL% and %LIBTOOL% while calling handle_source_transform.
(make_paragraphs): Define %NONLIBTOOL% by default.  Make sure
%transform settings override global settings.
* lib/am/depend2.am (%OBJ%, %OBJOBJ%): Define only if %NONLIBTOOL%.
* tests/libtool3.test: Augment to check Makefile.ins for unneeded
rules.
Suggested by Thomas Fitzsimmons.