How can I disable the default jQuery loading of WordPress 3.9.1?

Hi

I don’t wish to use jquery 1.11 but it comes default in WordPress 3.9.1, along with jQuery Migrate.
I dont want them. How can I get rid of that?

I dont want to see the following lines:

<script type='text/javascript' src='https://172.17.15.172/iswp/wp-includes/js/jquery/jquery.js?ver=1.11.0'></script>
<script type='text/javascript' src='https://172.17.15.172/iswp/wp-includes/js/jquery/jquery-migrate.min.js?ver=1.2.1'></script>

Functions.php:

// enqueue javascript
if( !function_exists( "theme_js" ) ) {
  function theme_js(){

    wp_register_script( 'jquery',
      get_template_directory_uri() . '/library/js/jquery-1.8.3.min.js',
      array('jquery'), '1.2' );

    wp_register_script( 'easing',
      get_template_directory_uri() . '/library/js/jquery.easing.1.3.js',
      array('jquery'),
      '1.2' );

    wp_register_script( 'transit',
      get_template_directory_uri() . '/library/js/jquery.transit.min.js',
      array('jquery'),
      '1.2' );

    wp_register_script( 'appear',
      get_template_directory_uri() . '/library/js/jquery.appear.js',
      array('jquery'),
      '1.2' );

    wp_register_script( 'mousewheel',
      get_template_directory_uri() . '/library/js/jquery.mousewheel.min.js',
      array('jquery'),
      '1.2' );

    wp_register_script( 'mixitup',
      get_template_directory_uri() . '/library/js/jquery.mixitup.js',
      array('jquery'),
      '1.2' );

    wp_register_script( 'scripts',
      get_template_directory_uri() . '/library/js/scripts.js',
      array('jquery'),
      '1.2' );

    wp_enqueue_script('jquery');
    wp_enqueue_script('easing');
    wp_enqueue_script('transit');
    wp_enqueue_script('appear');
    wp_enqueue_script('mousewheel');
    wp_enqueue_script('mixitup');
    wp_enqueue_script('scripts');

  }
}
add_action( 'wp_enqueue_scripts', 'theme_js' );