$ sudo apt-get update & apt-get upgrade
$ sudo apt-get install curl php-curl php-cli
$ curl -sS https://getcomposer.org/installer | sudo php -- --install-dir=/usr/local/bin --filename=composer

Usage sample

Assuming your project are running over Composer PSR-4 defaults, simply Require it on your composer.json

"require": {
    "intrd/php-common": ">=1.0.x-dev <dev-master"
}

And run..

$ composer install -o #to install
$ composer update -o #to update

Always use -o to rebuild autoload.

Now Composer Autoload will instance the class and you are able to use by this way..

require __DIR__ . '/vendor/autoload.php';
use php\intrdCommons as i;

$test="works!";
i::vd($test); //testing my var_dump() customized function