Refactoring task

The initial implementation (YangUtils) uses Module Reference as input which supposed to be persisted. Currently the Module information is not persisted with data fragments, but the reference to anchor is expected. 

1. Remove 'module' (see org.onap.cps.spi.model.DataNode properties)
2. Introduce DataNodeBuilder class (now in Fragment constructors)
3. xpath stored in fragment are NOT to include the anchor(name/id)
   Original it was proposed anchor name should be used as root for xpath property created for each fragment object -  mentioned in https://wiki.onap.org/pages/viewpage.action?pageId=92995793#CCSDK2756DM:[Spike]ProposeC&PSDataModel-2.2Genericschema(currentproposal)

Acceptance Criteria

1. Fragment classes removed from Java-service layer
2. Testware update inline with refactoring
3. Remove Module tabel from DB Schema