Add yacht exercise

[glennj]

No description provided.

[m-dango]

I want to have a think about this one for the categories arg, wondering if there's a better option than a string (thinking about how its done in Raku and Python)

[glennj]

Perhaps something like

package Yacht::Categories;

# exports ...

use constant {
    ONES => 1,
    TWOS => 2,
    # ...
    CHOICE => 12,
};

Or, do away with the category argument, and the generator calls a subroutine named after the category:

subs: ones twos ... choice
properties:
   score:
     test: |-
       use Data::Dmp;
       (my $name = $case->{input}{category}) =~ s/ /_/g;
       sprintf(<<'END', $name, dmp($case->{input}{dice}), $case->{expected}, dmp($case->{description}));
       is(
           %s(%s),
           %s,
           %s,
       );
       END