Adds the ability to add multiple checkbox and radio items

[octoper]

This PR adds the ability to add multipe checkbox and radio items at once.

Examples:

Checkbox

<?php

use PhpSchool\CliMenu\Builder\CliMenuBuilder;
use PhpSchool\CliMenu\CliMenu;

$callable = function (CliMenu $menu) {
    echo 'I am alive!';
};

$menu = (new CliMenuBuilder)
    ->addCheckboxItems([
        ['Item 1', $callable],
        ['Item 2', $callable],
        ['Item 3', $callable],
    ])
    ->build();

Radio

<?php

use PhpSchool\CliMenu\Builder\CliMenuBuilder;
use PhpSchool\CliMenu\CliMenu;

$callable = function (CliMenu $menu) {
    echo 'I am alive!';
};

$menu = (new CliMenuBuilder)
    ->addRadioItems([
        ['Item 1', $callable],
        ['Item 2', $callable],
        ['Item 3', $callable],
    ])
    ->build();

[AydinHassan]

@octoper thanks for the perfect pr, tests, docs, examples. Will merge when travis runs, probably next week at this rate (it's very slow) 😭

[octoper]

Thinking about making a PR to move from TravisCI to GitHub actions if it's good with you 😅

[AydinHassan]

I did try before but there were some problems with the tty stuff we do. It is definitely welcome if you would like to have a crack!

[octoper]

cc @AydinHassan hopefully TravisCI passed 😅

[AydinHassan]

Thanks @octoper !

[octoper]

Do you need both https://codecov.io and https://scrutinizer-ci.com ? (sorry that I'm mention that here but I don't know how to contact you) cc @AydinHassan

[mikeymike]

@octoper feel free to join us on Slack https://phpschool.herokuapp.com/

[AydinHassan]

We can drop scrutinizer, we have done for the other repos 🙂