History: Allowed ActiveSince in future.
Build 0.9.18.
Documentation.
Using ConceptMetadata for sharing concept implementation info (SQL column name and type).
Created SQL views for Polymorphic entity and its subtypes (#23).
Reference constraint for Polymorphic (#23).
Merge branch 'master' of https://github.com/Rhetos/Rhetos
Release 0.9.19.