[Data-modeling] Journal related types (draft)

[Ed Laurent]

I have created some types for those of us interested in keeping track
of journal articles. Please let me know if there is anything that
should be added or changed. I've included existing types whenever
possible. The draft journal related types are:

Journal article:
http://www.freebase.com/view/schema/user/spatialed/litcentral/journal_article

Journal issue:
http://www.freebase.com/view/schema/user/spatialed/litcentral/journal_issue

Journal:
http://www.freebase.com/view/schema/user/spatialed/litcentral/journal

-Ed