Fix the check_classes check for certain cases.

Examples:

File: modules/foobar/manifests/init.pp
Content: 'class bar { }'

File: modules/foobar/manifests/fail.pp
Content: 'class bar::fail {}'

These 2 examples do not throw the autoloader error while they really should.
Merge pull request #176 from vStone/feature/check_autoloader_layout_fix

Fix the check_classes check for certain cases.