the fix for de-917 ???

removed insane merging of ed org context rights for public entities.
#DS-917 new AT to check for unauthorized write_public access across ed_orgs
Merge branch 'ds-917' of https://github.com/inbloomdev/datastore into ds-917
fixed issue with OwnershipArbiter finding owner via nested subdocs relationships
Merge branch 'ds-917' of https://github.com/inbloomdev/datastore into ds-917
entities that have no body, or have an empty body are considered deleted

specifically, when a section is deleted its body is deleted, but the
studentSectionAssosciations remain in the document. Querying for this
document via the API returns a 404.
Add check to see if public entities are linked to the ed or hierarchy
#DS-917 updated ATs, definition only
Merge branch 'ds-917' of https://github.com/inbloomdev/datastore into ds-917
fixed pmd violation (no brackets for 'if')
so as not to break local test run
Merge branch 'ds-917' of https://github.com/inbloomdev/datastore into ds-917
Merge branch 'master' into ds-917
updated the tests for additional http methods. fixed "self" reference for determing ed_org access
making sure we can read public data fromany edOrg when we have the READ_PUBLIC right
mashed ben's commit. sorry, ben.
Merge remote-tracking branch 'origin/ds-917' into ds-917
altered invalidated acceptance test
Merge branch 'ds-917' of https://github.com/inbloomdev/datastore into ds-917
added a few additional cursory tests