feat: add support for old property syntax.

[apozharski]

This syntax is deprecated as far as I can tell, however matlab code tends to have a long shelf life.
Here is an example of this syntax in practice (again from the matllabdomain test suite):

classdef PropTypeOld
    properties
        link_name@char = 'none';
        pos@double vector = zeros(3,1);
        rotm@double matrix = zeros(3,3);
        idx@uint8 scalar = 0;
    end
end

It seems that Mathworks has purged documentation of this syntax (or at least I have not been able to find it) so this is an estimation from what I have seen in old projects and matlabdomain test suite. I have reached out to Mathworks support to try and dig up some official documentation however haven't heard back as of yet.

[acristoffers]

This was removed like 14 years ago, so I don't think they will care. I'll accept this PR once you remove the generated files and rebase. This is kind of a breaking change as the node is now quite different and tools that make use of it will have to be modified. I was trying to avoid that, but since there is a tool that needs it, I think it is fair to support it.

Just a request though: add an alias to $.identifier to the choice of matrix/vector/scalar. That is going to make it so 3 downstream projects don't need modification.