Remove CONTRIBUTING.md now the project is abandoned
Remove CONTRIBUTING.md now the project is abandoned

An alternative would be to have a contributing file which says the
project is abandoned like the README does.

Rimehch/php-exp,sebastianbergmann/money,HSarode-Compumatrice/money,ankahla/jenkins-phpunit-example,ankahla/jenkins-phpunit-example,terryhuangbo/ut,balsing/Money