Improved outline for erroneous intermediate status where the name of
something could be potentially null, which should not lead to a NPE.
Imports in the outline view are encapsulated in a container
Merge branch 'v0.11.x_bugfix'
Merge branch 'outlineInContainer' of https://github.com/tilois/integrity
into tilois-outlineInContainer

Conflicts:
	de.gebit.integrity.dsl.ui/src/de/gebit/integrity/ui/outline/DSLOutlineTreeProvider.java