BZ-986000 - DRL-to-RuleModel marshalling improvements

(cherry picked from commit 121312df459ab3d62aee808ba1c08e455c6fd862)

Conflicts:
	drools-wb-screens/drools-wb-drl-text-editor/drools-wb-drl-text-editor-client/src/main/java/org/drools/workbench/screens/drltext/client/editor/DRLEditorPresenter.java
BZ-986000 - DRL-to-RuleModel marshalling improvements

(cherry picked from commit 4be6fb31f4963c08e9dae1fd43c997b6ed71a2fb)