Take the opportunity of the Motor 2.0 release to drop any deprecated APIs scheduled for removal in PyMongo.

done Verify that running Motor 1.2 and PyMongo 3.x with deprecations enabled raises deprecation warnings for these. I never did significant work in Motor to deprecate old methods, I relied on PyMongo's warnings.

done PYTHON-1302 Remove MongoClient.kill_cursors
done PYTHON-1305 Remove MongoClient.get_default_database
done PYTHON-1307 Remove support for SON manipulators
done PYTHON-1309 Remove helpers for getLastError and friends
done PYTHON-1314 Remove Database.authenticate and Database.logout
done PYTHON-1316 Remove Database.eval (database.SystemJS never supported)
done PYTHON-1318 Remove Collection.initialize_unordered_bulk_op and Collection.initialize_ordered_bulk_op
done PYTHON-1319 Remove Collection.ensure_index
done PYTHON-1320 Remove write methods deprecated in PyMongo 3.0
done PYTHON-1322 Rename py3compat.py to py2compat.py (rename motor_py3_compat to py2_compat)
done PYTHON-1323 Remove Collection.group
not in Motor code: PYTHON-1326 Remove the "useCursor" aggregate option
done PYTHON-1587 Remove database_names and collection_names
done PYTHON-1588 Remove MongoClient.close_cursor
done PYTHON-1592 Remove Collection.parallel_scan
done in MOTOR-204: PYTHON-1312 Remove user management helpers
done PYTHON-1580 Remove MotorCollection.count
already done PYTHON-1321 Remove MongoReplicaSetClient
never supported: PYTHON-1301 Remove support for cursor managers
not in Motor code: PYTHON-1410 Remove "safe" legacy messages.
not in Motor code: PYTHON-1484 MongoClient option validators should not change option values
not in Motor code: PYTHON-1514 Handshake changes for SDAM and Auth
not in Motor code: PYTHON-1363 Remove unused "retrieved" parameter from CommandCursor

done Delete the migrating-to-motor-1 guide, write migrating-to-motor-2

done Reenable enterprise auth tests (see PYTHON-1601)