Py2neo

- More result hydration performance improvements

- Added basic bulk load functions
- Sped up result hydration for large result sets
- Added support for Python 3.9
- Numerous bug fixes

- Fixed bug with HTTP calls returning non-200 response
- Allowed HTTP to detect bad credentials on `Graph` construction, as with Bolt

- Added support for Neo4j 4.1
- Added experimental routing support
- Removed node and relationship caches
- Removed Graph/GraphService instance reuse
- Added test to ensure correct operation with multiprocessing
- Improved connection management and logging
- Added explicit "readonly" transaction mode
- Added `triples` method to OGM RelatedObjects
- Fixed cursor preview bug with empty results

- Added support for Neo4j 4.1
- Added experimental routing support
- Removed node and relationship caches
- Removed Graph/GraphService instance reuse
- Added test to ensure correct operation with multiprocessing
- Improved connection management and logging
- Added explicit "readonly" transaction mode
- Added `triples` method to OGM RelatedObjects
- Fixed cursor preview bug with empty results