Update to latest git and add one extra patch:
- Fix the order in which builtins are loaded.
- Fix crash on undefined variable actual_types in check_argument_count (replaces local patch)
- Fixes for Generator support
- Fix crash in check_overlapping_op_methods
- Hopeful fix for #1002 (lxml trouble)
- No longer need to pin flake8 version.
- Find partial types anywhere in the stack. (not yet committed upstream)