Documentation about Vim mode

[Matthias Kilian]

Hi,

I think the note on Vim 6.2 in the documentation (INSTALL.html)
should be changed to Vim 6.2.073. At least for 6.2.0, I had to eidt
~/.vim/filetype.vim, and the ftdetect mechanism is mentioned in Vim
patch 6.2.073.

I send this to lilypond-user since some other users may also have
forgotten to apply recent patches to Vim and still have Vim 6.2.0 ;-)

Ciao,
        Kili