Multicolor - Add Alpha Option?

[bawright]

Issue description:

Alpha (true/false) for multicolor control?

Version used:

2.3.7

Using theme_mods or options?

theme_mods

Code to reproduce the issue (config + field(s))

Kirki::add_field( 'my_config', array(
    'type'        => 'multicolor',
    'settings'    => 'demo-multicolor',
    'label'       => __( 'Multicolor', 'text_domain' ),
    'section'     => 'demo',
    'priority'    => 10,
    'choices'     => array(
        'bg'        => __( 'Background', 'text_domain' ),
        'text'      => __( 'Text', 'text_domain' ),
    ),
    'default'     => array(
        'bg'        => '#000',
        'text'      => '#fff',
    ),
) );

[aristath]

@danielortiz was kind enough to submit a pull request that was just merged.
You can now set 'alpha' => true, in your control.
Fix will be included in 3.0.9 when it is released.