#770 classCode @scheme punctuation

[Martin de la Iglesia]

The description of the @scheme attribute in http://www.tei-c.org/release/doc/tei-p5-doc/en/html/ref-classCode.html reads: "identifies the classification system in use, as defined by for example by a taxonomy element, or some other resource.."
One full stop at the end should be enough.

[Martin Holmes]

Fixed in git 6850b94..d14e674. Closing. Thanks Martin!