Reworded --diff flag help string to improve clarity (which created misunderstandings in Issue #407)
Reworded --diff flag help string to improve clarity (which created misunderstandings in Issue #407)

ABaldwinHunter/pep8-clone-classic,pedros/pep8,MeteorAdminz/pep8,pandeesh/pep8,PyCQA/pep8,codeclimate/pep8,asandyz/pep8,zevnux/pep8,ABaldwinHunter/pep8