Added tests for

TODO:

- [ ] merge branch for parent attributes
- [ ] finish tests
- [ ] apply parent/chile link terminology
- [ ] implement CLI tests
- [ ] implement CLI
Merge branch 'master' into child-link-publishing.
Test cleanup.
Renamed find_rlinks() to find_child_links().
Added Item.find_child_items/documents().
Added child aliases.
Added '--with-child-links' option.
Merge pull request #57 from jacebrowning/child-link-publishing

Add child (reverse) links to reports.