[texdoc] texdoc trip

[Karl Berry]

Hi Manuel (are you there? still want to maintain this?),

texdoc -l trip returns:
 1 /usr/local/texlive/2013/texmf-dist/doc/context/third/simpleslides/styles/Framed-stripe.pdf
..
12 /usr/local/texlive/2013/texmf-dist/doc/generic/knuth/tex/tripman.pdf

I suggest that, in the absence of any better match, "texdoc foo" should
prefer foo* to *foo*.  If you see what I mean.

Thanks,
Karl