PSR1 recommends that each class should be in its own file to aid autoloaders.
Having each class in a dedicated file usually plays nice with PSR autoloaders
and is therefore a well established practice. If you use other autoloaders, you
might not want to follow this rule.
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.