line length feature

[MaxOstrowski]

It would be cool to have --line-length option to specify a maximum length of a line and avoid a linebreak after every used predicate.
A default of --line-length=0 would still produce the result as it is produced before but other output could be possible like:

% Check lower and upper bounds via "Sinz counter" on selected varying atoms
index(A, I) :- vary(A),
               I = #count { B : vary(B),
                                B <= A },
               not bounds(0, 0).

counter(I, 1) :- index(A, I), bounds(L, U),
                 L <= I, selected(A).

[sthiele]

I was thinking about something like that but had no time to finish it. See:

clingofmt/src/lib.rs

Lines 425 to 429 in 6470802

	if state.in_termvec == 0 && !state.is_show
	/*|| buf.len() >= MAX_LENGTH */
	{
	flush = true;
	} else {