Specify data shape for article notifications

[csarven]

Article in the generic sense of the word. It could include manuscripts, scholarly articles, notes, slides, reviews, thesis etc. There may be some overlap with issue #9 but that's fine.

[csarven]

MUST include:

# No need to declare the URI of the notification.
<>
  a as:Announce ;
# A valid xsd:dateTime.
  as:updated "2017-09-05T21:11:58.611Z"^^xsd:dateTime ;
# CC0 license must be declared here.
  schema:license <https://creativecommons.org/publicdomain/zero/1.0/> ;
# URI of the article that's being announced
  as:object <http://csarven.ca/dokieli-rww> .

# A class along the lines of schema:ScholarlyArticle, sioc:Post,
# foaf:Document, sioc:Post, biblio:Paper, bibo:Document, as:Article.
<http://csarven.ca/dokieli-rww>
  a schema:ScholarlyArticle .

SHOULD include:

# URI of the agent (but not the software) that sent the notification.
<>
  as:actor <http://csarven.ca/#i> .

# URI of an open/free culture license on the article is expected here.
<http://csarven.ca/dokieli-rww>
  schema:license <https://creativecommons.org/licenses/by/4.0/> .

MAY include:
Anything else that may help with the reuse of this notification or discovery of the resources it refers to. This doesn't mean that the body of the referred resources should be copied here.