Django-pg-bulk-update

Bug fixes
1. Fixed issue 84 : functions used as default field value are now handled correctly

Requirements
1. Replaced psycop2-binary with psycopg2 in requirements files

Testing
1. Added django 4.0 to GitHub Actions

Features
1. Added ability to use django expressions as set functions

Tests
1. Fixed tests by issue 70

Bug fixes
1. Fixed issue 71 :now if set functions which don't require a value get it from user's input it is ignored

Features
1. Optimized batching mechanics
2. Minor refactoring

Bug fixes
1. Thanks to dhendry, user `set_functions` are now prior to standard `NowSetFunction` when field has `auto_now` or `auto_now_add` options.

Compatibility
1. Fixed python 3.10 compatibility (dhendry)

Testing
1. Removed python 3.5
2. Added python 3.10 and PostgreSQL 13

v3,4,3
Bug fixes
1. Fixed django 3.2 compatibility

Compatibility
1. Optimized library requirements in order to install less dependencies in actual python versions

Bug fixes
1. issue-63 fix by ryanhennig: already quoted table names formed wrong SQL
2. Partially fixed `auto_now` tests bug with local timezone differring from UTC

Documentation
1. Added manual for running unit tests locally (by ryanhennig)