Theme Customizer Boiler plate you can use in your themes. For detailed explanation, check WP Explorer.
Copy entire '/customizer-boilerplate' directory into your theme's directory and include 'customizer.php' from your theme's functions.php':
require( get_stylesheet_directory() . '/customizer-boilerplate/customizer.php' );
Then you can change contents of '$options' array in 'options.php' file by using 'thsp_cbp_options_array' filter hook.
If you'd like to place Customizer Boilerplate in another folder inside your theme folder (e.g. /inc/customizer-boilerplate) make sure you hook into 'thsp_cbp_directory_uri' filter hook and change default customizer path (see 'thsp_cbp_directory_uri' function in 'helpers.php').