feval extensions for working with multiple output arguments

Allows any number of output arguments to be returned from a function in any order and optionally gather to a cell array.

A common question for MATLAB users is how to get only arguments beyond the first from an output argument list. For example, to simplify the syntax:

[~,ind] = max(A);

to remove the unused argument.

This question becomes more than a matter of convenience when anonymous functions come into play. For instance, how could one write an anonymous function to return the difference of the elements of a vector immediately preceding and following the maximum from the maximum itself?
I.E. f([3 5 4]) == [-2 -1]

The functions in this submission assist with this task by allowing manipulation of the count, order, and format of multiple output arguments.

fevali(iout, fn, ...) - this function re-orders and/or downselects the output argument list

For example, instead of:
[mv,iv] = max(A);
one can do
[iv,mv] = fevali([2 1], @max, A);
or simply
iv = fevali(2, @max, A);

fevalic(iout, fn, ...) - this function not only re-orders the output argument list, but returns all output arguments as a single cell output rather than in varargout list. This enables access to all outputs within an anonymous function.

For example:
c = fevalic(c[2 1], @max, A);
%c{1} contains index of max and c{2} contains the max itself

This can be used to write the earlier requested anonymous function:
prepostmaxdiff = @(x) feval(...
@(x,c) x([c{2}-1 c{2}+1]) - c{1}, ...
x, fevalic(1:2,@max,x) ...
);
% the first feval evaluates the indexing and difference expression
% the fevalic call returns both outputs of max in a cell array for use in the feval
% c{1} has the max and c{2} has the index of max

fevalnc(nout, fn, ...) - This function is simply a shortcut of fevalic(1:nout, ...).

This submission is similar to https://www.mathworks.com/matlabcentral/fileexchange/53552-fevaln-feval-with-control-of-the-order-of-the-outputs, but adds additional capability to return arguments as a cell array.

Developed and tested on 2019b, but should work back to much earlier versions (as long as argument list expansion is supported).