use `forward-line', not `next-line'
comments
improved the indentation scheme.

it now recognizes the *last* lines of continued commands, as well as the
first.  as an example, the following should indent under "plot," not
"tan".

   plot sin(x) w l,\
        cos(x) w l,\
        tan(x)
started a tests directory
store multi-line command regexp in a variable.
added a docstring
let* no longer neded
comments
take explicit newlines out of regexp.

this makes it look even worse, but things like fill-paragraph or
indent-defun won't screw it up now
fixed indentation bug and updated comments

it's a pretty gnarly regexp, though :(
bump version number

I think fixing the indentation counts