Simplified the EntryModelGenerator
Polymorphic Keywords
Polymorphic keywords migration
Fix some errors in pages module
Fix some pages bugs for page types

Keywords still is broken here - updated methods no doubt
Merge branch '2.3/develop' of github.com:pyrocms/pyrocms into 2.3/develop

* '2.3/develop' of github.com:pyrocms/pyrocms:
  Fix some pages bugs for page types
  Fix some errors in pages module
  Polymorphic keywords migration
  Polymorphic Keywords
  Simplified the EntryModelGenerator
french translations for addons module