Backwards-incompatible changes:
* Identify sessions by their identifiers instead of their names (update your `get_session_list()` methods)
Improvements:
* Check for the presence of a `get_session_list()` method instead of `check_sessions = True`
* Resolve an event's participants and its agenda items' related entities 206, 207
* Accept an organization name in `Person.add_membership` for the second parameter 233
* Accept `datetime` dates wherever string dates are accepted 218
* Improve error reporting 214, 230, 231
* Compatible with Django 1.10
Fixes:
* Allow people to hold multiple posts in an organization 244, 247
* Add a `primary_org_name` parameter to `Person.add_term`, to disambiguate organizations with the same classification 223
* Update an object if the explicit order of its related objects has changed 242
* Touch an object's `updated_at` whenever its related objects are updated 226
* Correctly resolve a new person with the same name 232
* Don't raise a resolution error due to multiple matches in cases where zero matches are acceptable