Treat "No styleguide reference." as KSS Sections

No styleguide reference KSS Comments were previously not treated sections
even though they are valid KSS Comments. Updates Parser::isKssBlock to
return true for "No styleguide reference". Updates tests.

Adds hasReference to Section that returns a boolean value for whether or
not a Section has a styleguide reference. Adds related tests.

Removes all "//" prepends in the SectionTest.php file as all "//" should
have been already stripped by the CommnetParser.