reciprocity/ggrc-core — pull request #1135 by danring (2014-03-24 19:56:33+00:00)
Title: Differentiate Section from Clause; split Clauses/Contracts

* Adds `sections.type` column to be either `Section` or `Clause`
* Adds `SectionBase` and `Clause` models to handle polymorphism of
`Section` and `Clause` models
* Adds `DirectiveSection` to map `Directive` objects to `Section` and
`Clause` objects non-directly (currently only used for `Clause`)
* Add `Clause` to mappings and widget/controller definitions and
"join_descriptors"
* Add `Clauses` to LHN search list