Added so equals and hashcode is generated in models.

[denvitaharen]

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I have added so equals and hashCode is generated to the models. It's possible to disabled it if someone doesn't want it.

@ricardozanini I created an new branch and pull request, it was easier and faster for me to do that.

The result looks like this:

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        Animal model = (Animal) o;

        return Objects.equals(born, model.born) &&
        Objects.equals(deceased, model.deceased);
    }

    @Override
    public int hashCode() {
        return Objects.hash(born,
        deceased);
    }

[denvitaharen]

    /**
     * Compares this object to the specified object. The result is
     * {@code true} if and only if the argument is not
     * {@code null} and is a {@code Animal} object that
     * contains the same values as this object.
     *
     * @param   obj   the object to compare with.
     * @return  {@code true} if the objects are the same;
     *          {@code false} otherwise.
     **/
    @Override
    public boolean equals(Object obj) {
        if (this == obj) return true;
        if (obj == null || getClass() != obj.getClass()) return false;

        Animal model = (Animal) obj;

        return Objects.equals(born, model.born) &&
        Objects.equals(deceased, model.deceased);
    }

    /**
     * Returns a hash code for a {@code Animal}.
     *
     * @return a hash code value for a {@code Animal}.
     **/
    @Override
    public int hashCode() {
        return Objects.hash(born,
        deceased);
    }

I realized that I hadn't written any javadoc for the new methods, so I added it now. It took some inspiration from the String and Long javadoc and rewrote so it fits this in.

[mbard]

Excellent, I really need equal/hashcode

[ricardozanini]

LGTM!