Fix docs

[boosh]

The docs are wrong. Instead of:

<div x-tour:bottom="{step: 1, title: 'Example title', description: 'This is the description'}"></div>
<div x-tour:top="{step: 2, title: 'Example title', description: 'This is the description'}"></div>
<div x-tour:left="{step: 3, title: 'Example title', description: 'This is the description'}"></div>
<div x-tour:right="{step: 4, title: 'Example title', description: 'This is the description'}"></div>

It should be:

    <div x-data>
        <button x-tour.start>Start tour</button>

        <div x-tour.bottom="{step: 1, title: 'Example title', description: 'This is the description'}"></div>
        <div x-tour.top="{step: 2, title: 'Example title', description: 'This is the description'}"></div>
        <div x-tour.left="{step: 3, title: 'Example title', description: 'This is the description'}"></div>
        <div x-tour.right="{step: 4, title: 'Example title', description: 'This is the description'}"></div>
    </div>

Without x-data, the plugin is never started, and it needs to use dots not colons on x-tour.