Move old unit tests for Section
Remove outdated comments
Add missing operators to nix::Section
Create basic unit test for nix::Section
Make acceptAllFilter() a template and move to util
Implement section access methods for Sections
Remove tnode because it is no longer needed.
Implement accessors for propertis on sections
ImplContainer: fix constness of operator== and operator!=
Section: the property link now handles Sections

File: add findSections method and remove old one
Section has now a working getter for parent
Section: implement method inheritedProperties()
Merge pull request #53 from stoewer/master

Missing features and tests for Section 

Part of issue #25 (Unit tests)