Fixed hardcoded path in json testcase
Builder refacturing to fix check for errors in items defined in 'build'
Builder refacturing to fix check for errors in items defined in 'build' - tests
Changed test group name to get 100% coverage
Minor cleanup
Don't chdir in test script, it confuses emacs
Builder refactoring and fix for contained_in linking when multiple objects created in builder (which would normally be the case:)
 - Objects created in builder may be cloned to fix up contained_in after being moved to built objects
 - An original object created under a builder may have contained_in == None. If item methods depends on contained_in, the (cloned) item(s) must be accessed via the resulting object tree. A reference to the original item is invalid.