Remove core models article, this requires Image and Source
Remove auto import opps core mdoels article to opps article
move core init to opps init
Remove core models package
create core models file
Change installed app, opps.core to opps
Remove opps core test suite
Add Article abstract in opps article models
fix core init package
Merge branch 'master' of github.com:oppsproject/opps

Conflicts:
	opps/core/models/article.py
Refix issue #41, fix by @seocam