Singular interpreter shows different behaviour for procedures and kernel commands

[steenpass]

> ring r = 0, x, dp;
> ideal i = 256x;
> bigint p = 7;
> farey(i, p);   // everything OK until here
_[1]=1/2x
> list arguments = list(i, p);                        // now this list applied to
> proc command(ideal i, bigint p) { farey(i, p); };   // this procedure
> command(arguments[1..size(arguments)]);             // works fine,
_[1]=1/2x
> farey(arguments[1..size(arguments)]);               // but this does not work.
   ? error occurred in or before STDIN line 8: `farey(arguments[1..size(arguments)]);`
   ? last reserved name was `size`
   skipping text from `;` error at token `)`
> 

The problem here is that syntax of the form 'command(arguments[1..size(arguments)]);' has been used in parallel.lib so far as a generic way to apply arguments given by a list to some command.

[steidel]

Implement call_proc_list.