import texinfo 4.8 into the tree.
(okay theo, kettenis)

TeXinfo 4.2, much more robust html (and other formats) output, and a few
features that new FSF programs will need (e.g., gcc snapshots).

looked at by fgs@, thanks.

TexInfo 4.0. New manpages, can create html.
A bit more grumpy about bad texinfo, though.