Improve code examples

[noplanman]

Touch up and complete code examples, adhering mostly to WordPress style guide.

The main thing that I haven't added are inline comments ending with periods and the spaces between parenthesis:

// An inline comment here
$following = __('This style');

// A WP styled comment.
$following = __( 'WP style' );

@jjgrainger Shall I change them all to make it 100% WP style guide compatible?

[jjgrainger]

@noplanman Thanks for this, I'm happy with the changes you've made.

Maybe we could review the updating code examples to 100% adhere to the WP style guide later. For now, I would like to get all your pulls merged to benefit from the great work you've done!

Thanks 👍