Bootstrap Genesis - add the logo in the nav to the customizer. This file can be dropped into the wp-content/mu-plugins/ directory (note: you may need to create the mu-plugins folder within wp-content if it does not already exist)

bsg-customizer-navbar-logo.php

<?php

// add customizer controls
add_action( 'customize_register', 'bsg_navbar_brand_logo_customize_register' );
function bsg_navbar_brand_logo_customize_register( $wp_customize ) {
    $wp_customize->add_setting( 'brand_logo',
         array(
            'default' => '',
            'type' => 'theme_mod',
            'capability' => 'edit_theme_options',
            'transport' => 'refresh',
         )
    );

    $wp_customize->add_control( new WP_Customize_Image_Control(
         $wp_customize,
         'bsg_brand_logo',
         array(
            'label' => __( 'Navbar Logo', 'bsg' ),
            'section' => 'title_tagline',
            'settings' => 'brand_logo',
            'priority' => 10,
         )
    ) );
}

// show logo if it has been added via customizer
add_filter( 'bsg_navbar_brand', 'bsg_customizer_add_navbar_brand' );
function bsg_customizer_add_navbar_brand( $output ) {

    $brand_logo = get_theme_mod( 'brand_logo' );

    // check $brand_logo is set
    if ( ! $brand_logo ) {
        return $output;
    }

    $output = '<a style="padding: 0 15px;" class="" id="logo" title="' .
        esc_attr( get_bloginfo( 'description' ) ) .
        '" href="' .
        esc_url( home_url( '/' ) ) .
        '">';
    $output .= '<img style="width: 104px; height: 46px; margin-top: 3px;" src="' .
        $brand_logo .
        '" alt="' .
        esc_attr( get_bloginfo( 'name' ) ) .
        '">';
    $output .= '</a>';

    return $output;
}