Fix issue #138
Fix issue #138
Remove the relation if target collection was removed.
Merge branch 'issue_138' of github.com:collective/collective.cover into issue_138

Conflicts:
	src/collective/cover/tests/test_collection_tile.py
improve testing and changelog...
Merge branch 'master' into issue_138

Conflicts:
	docs/HISTORY.rst
Merge branch 'master' into issue_138

Conflicts:
	docs/HISTORY.rst
fix change log
Merge pull request #163 from collective/issue_138

fixes #138